There wasn't one decision. There were many along the way.
DD happened because I had noticed that my husband was acting very odd towards me and in general. You can read some of my other threads to get more of our story, but the Reader Digest version is that for financial reasons he had taken a long term contract that caused him to basically live in another state for a little under two years. While his job had often caused him to travel for weeks at a time, it was rarely more than a 2-6 weeks with long stretches at home in between. We had always been very close and loving (dated on and off since we were 13 and 14 - got together again at 19 and 20 and been together every since.) He hated the time apart and wanted me to join him, but I was helping my parents and our daughter at the time with situations that they were struggling with. During the last year of his time there, he and a co-worker began hanging out as friends - which led to an on/off affair for the last 10 months. During the last few months before he came home I had noticed a difference in the way he interacted with me. He found fault with me in ways he NEVER had in 25+ years together and seemed very uncomfortable in his own skin whenever we were around each other (short visits.) Once the contract ended and he came home, it was clear something was off.
After about 2 weeks of trying to reconnect and everything feeling very awkward and strange between us, I finally just straight up asked him what was going on. He had been really struggling with the dishonesty (it was easier when he wasn't having to look me in the eye very often and he could keep the worlds separate) - so he just blurted it out, surprising both him and me. He was extremely confused because when it had started he'd always thought it was going to be a very short term thing that would end when he came home and be tucked away in a box in his head. It never occurred to him that the guilt would make it nearly impossible to connect at a deep level with me, or that it wouldn't be easy for either him or the AP to stop the relationship on a dime. He really had sold himself a story where they'd enjoy their time together and then move on at the end of the contract (no fuss, no muss.) He's normally an intelligent man but when it comes to emotions and life... well not so much - clearly.
I went straight to divorce. My feelings for him shut down and I couldn't even remember why I'd ever loved him. Even though when he blurted it out he didn't seem to know what he wanted, within 24 hours he was asking if we could work it out. If I would consider staying. While I said no, I think a part of me wanted him to fight for me, for us. When he seemed resigned to my decision it made me even more hurt and angry. For him, he thought it was inevitable that there was no way forward - that I'd never be able to forgive him.
Then something unexpected happened. The job that was supposed to be done had a revision - and he needed to go back for a short period. This was about four days after DD. He'd be working side-by-side with the AP again. I was still in the divorce mindset and told him to go - he could consider himself single and that I would as well (I'd taken my wedding ring off at this point). He was gone 10 days. This time is still a painful memory for me - and yet I believe it was a critical turning point for us. Without the source of my pain and anger in front of me, I was able to reflect on my marriage - it's strengths and weaknesses - and what I really wanted going forward. During this time was when I realized that I might not be ready to walk away. And he had to face the reality of what he'd done and what it was about to lead to. Everything looked different. Suddenly he was looking at the AP and his choices from a different perspective. It had seemed like a good "add-on". But now it was going to be the only thing he had left. He was horrified. He exchanged something of immense value for something that he didn't even want long term. He realized that he was on a road he didn't want to travel. There is a lot more to the story, but suffice to say, we both went on a journey of self-discovery in those 10 days. We both came back from it committed to TRYING.
I don't think either of us was sure that it could ever be good again, but we knew we had to give it a shot before walking away. And in our case, I am so glad we did. We are in a really, really good place But please understand, it was a VERY LONG, HARD road to get there. It has been suggested that it might be easier to just get a divorce and start over with someone new that you have no history with BECAUSE this road is so difficult. And frankly, it may well be in MANY cases.
There were a lot of things that went into my decision to try:
1. First - I needed to know he was really committed to rebuilding for the right reasons (not to save face, not to use me as a bridge to repair his reltionship with our daughter, etc.). I had no desire to "keep" him if he didn't want to be there. I wanted to be deeply loved and cherished - and was committed to offering that in return. If that was how he felt about me but had lost sight of it amidst all the hardships of the past years, that was something we could work with and learn to safeguard and protect in the future. But if not, for ME, it wasn't worth rebuilding. I know many other people may make different choices and I support that. But for ME, I knew it would never be enough for us to be good friends and partners. I needed and wanted a deep love connection. I had no idea if I could ever be that vulnerable with him again - but I was willing to try - IF, and only if, I was what he really wanted and was willing to work hard to achieve.
So I asked him to search his soul and figure out what he wanted. He could be with me but only if he wanted to be the kind of partner I wanted.
He could leave and be with her (or with someone else), and that was okay too. He didn't need to feel guilty about that choice, because I would be okay. i was giving him an out. But then he would be the father of my child, nothing more. I would move to create a life without him and he would have no part in it other than where it came to our daughter. Maybe someday 10 years from now we could be friends, but I was making no promises.
I made it clear that I felt I deserved to be happy and in a relationship that was supportive and honest. And that I was going to move towards that - with or without him. I told him that I loved him deeply and hoped it would be with him (this was hard because I hated being vulnerable - but it was also true and I decided truth had to win out over my ego). However, I also loved and valued myself - and I owed it to myself to not settle for less than I was worth. And I would not model less to our daughter either.
This was NOT a ploy. It was the plain, honest truth. I was also clear that I had NO idea if it would work. I could make no promises that I would get over it or that our relationship could/world survive. The only thing I could promise is that I would TRY - that I would do everything in my power to heal myself and to rebuild our marriage.
2. While he was doing his soul-searching - I was doing a lot of my own. I forced myself to take a very cold, hard look at my marriage and my husband. To evaluate it with a far more discerning eye. I also made myself look at my own reasons for wanting to stay. Was it for love? If so, was it a healthy love - did it give more than it took the vast majority of the time? Was it to save face? To not feel like a failure? on and on... I was unrelenting with myself and him. I questioned EVERYTHING. Slowly, I came to be sure of only a few things. That I loved my husband and that the vast majority of our marriage HAD been healthy and happy. That he - and the marriage itself - had given more than it had taken. It wasn't perfect - but it had made me feel happy, confident and loved for more than 80% of the time.
However, I was equally sure that I would never be able to trust my husband again unless he unraveled the thinking that had let him make this choice - and learn a LOT of emotional skills he'd previously lacked. In short - he had to go to therapy - and I had to SEE real changes in specific areas of our life together. Or no matter how much I wanted to move forward together, it would be impossible.
So I sat him down and told him exactly that. I also told him that I knew he might choose not to do it. He had adamantly rejected it in the past even when it was clear that he needed it. And I had relented. II hadn't wanted to be "controlling." This time I told him - if you don't, I can't stay. This isn't about punishing you or controlling you - it is about MY SAFETY and PEACE. Nothing more. I can't wait for the next time the voices in your head get so loud that you act out in some way. You either make peace with your voices in a way that I can FEEL and SEE - or I am out. This is non-negotiable.
3. Even once I was clear why I wanted to try, and what my boundaries for this were.... AND he'd determined that he was 100% committed to rebuilding and not only agreed to my boundaries, but started taking active measures to meet them - I still couldn't commit 100%. Because these weren't changes that were going to take place overnight in him. Nor would I have any way of knowing if I'd really be able to forgive him or trust him enough to open to the kind of deep love I desired for quite a while. At first this uncertainly nearly drove me mad.
But somewhere on this forum someone (I think it was KeepaBuzz) suggested setting a timeframe (6 months) where you didn't have to decide. That made sense to me. I would actually set an alarm in my phone. When the fear would come and I'd begin to worry that I was wasting my time and his... I'd remind myself that it wasn't time to make a decision yet. When my alarm went off, I looked back at the last 6 month to see if we'd made any progress. I searched my soul to see what I wanted more - to leave or stay. Since I still wanted to stay (and we were making progress) but were still a LONG way from ideal, I chose to set another alarm for another six months. Just after 20 months (the third 6 month period) I realized we'd made so much progress that I was fully committed again.
But it took THAT long before I stopped setting alarms. And that was only because both my husband and I separately, and together, had worked REALLY hard - on ourselves (first) and on our relationship (throughout - but more after we addressed our core issues individually - my trauma and his unraveling his real reasons why.)
If he hadn't surprised the heck out of me and actually finally stopped running away from himself and instead dove deep into his own head to sort out his issues... I might well still be setting alarms. Or be gone.
There is only so much WE, as BSs, can (or even should) do to save the marriage . A marriage is a two person job and if one person is unwilling to do their part it will not survive long term - or if it does the other partner will be very, very unhappy. No way to live.
There is a LOT more that I suggest for YOUR specific journey. To make sure you heal with or without your husband. But this is long enough and I hope I've answered your specific question.
And last but not least - I am VERY happy we decided to stay together. I am really enjoying life (3 years+ post DD) and my husband has done a great job of continuing to become more loving, more kind and more compassionate. I actually LIKE and LOVE the person he is today more than the boy I originally fell in love with. I hate how we got here - but I still love the place we are at. Our relationship makes me feel loved and supported. I realize that there is a risk that some day he will fail me again and I will regret those words - but I take that risk loving anyone. And I feel that the changes I have witnessed in him have been very real and true, so in an odd way - I think I may be safer in his hands now than I have ever been. Maybe even safer than in someone's hands that has never faced their demons and learned to tame them.
PS - While this is a happy ending, I still feel the need to reiterate it was a VERY, VERY, VERY, VERY long road with a BOATLOAD of work on both our parts to get here. Only unwavering commitment on BOTH sides can lead to this outcome together. But it is very possible to achieve the same happy place on your own if your partner is unwilling or unable. Don't lose sight of that.