A couple thoughts:
1. I agree with everything that #BorealJ said. The whys are a lot more important than the details at this point. The whys tell you and her what needs to be addressed/changed/healed in order to move forward.
2. I know it may feel like she's lying when she changes/doesn't remember details, but I honestly doubt it. For a couple good reasons.
First, people who suffered trauma as children (and even sometimes as adults) typically have developed significant coping mechanisms. In many cases it is well beyond compartmentalization. It's more in the realm of disassociation. So when something triggers shame in them (which cheating would likely do) - it's as if it is happening to someone else. If an event DOESN'T trigger shame, it will be processed normally - there is no barrier to the normal cognitive functions.
A lot of people on affair forums discount this because they see it as an excuse made by the WS. i have treated/known far too many with childhood abuse to believe that. Children have NO defenses. Their brains aren't fully formed and they are dependent on us for their survival. They accept nearly anything told to them by an adult as FACT (why they can believe in Santa.) So if we can accept that grown men could be traumatized by war, how could we not accept that people who were abused as children would not suffer on-going issues resulting from it. And the abuse does not need to be physical - I have known some people who's parents waged psychological WAR on them as kids. They never laid a hand on them but they messed their heads up so bad that I would take being a BS 20 times over what they endured because at least I am a grown adult with a fully formed identity.
Second - these were a LONG time ago in many cases. I am in no way trying to give your wife a pass - what she did was awful and the fact that she did it more than once is devastating. And yet... I really don't think she's lying about not remembering some of the details you want. For instance, I am the BS. Over the past three years, my husband and I have had numerous discussions about the affair. Discussions that I asked for and needed to have. In each case, I listened and responded to all of his thoughts/feelings/answers. I WANTED to retain every single thing he said. But because of the heightened state of stress I was naturally experiencing in these conversations, I repeatedly forgot/couldn't remember CLEARLY a solid 50-60% of what he said. And I'd have to ask him many of the same questions ALL OVER again - because even though I remembered asking, I couldn't remember his answer.
So if I couldn't remember information I wanted
to retain due to a heightened emotional state... what are the chances that a WS could have the same issue? And to add another element to that, I can't remember GOOD, happy important memories from 20 years ago during a 3 year span where i was in poor health and got very little sleep. Sleep SIGNIFICANTLY effects how well memory is preserved, it is a critical part of the neurological process that takes place to store and categorize memory. So her medical issues could be also playing a very real role.
3. For your own well being you will need to find a way to accept that there will be things you may never know. But if she can't remember them - then you are BOTH in the dark. And it appears that if she's told you about all 4, she's at least attempting to tell you what she does remember - unless she's only confirming things you already found. If that is the case, I'd be more concerned. But if she's volunteered information that you had not discovered, and may never have been able to find - then she's likely being about as honest as she can.
Truthfully, I will say that as a BS, I did reach a point where I did not keep asking for more details. While I needed far more details than a lot of people, I still reached a point when I realized that more information about the past was not going to inform my future.
I know it is hard to quiet the voices in your head - but this is a BIG, BIG part of a BSs healing. Learning to control our own mind and cultivate mental and emotional habits that serve our well being rather than hurt us. Are you seeing a therapist? They often have techniques that they can teach you that are tailored to your personality or situation that can help you gain control of your wandering/mulling mind.
If you aren't seeing a therapist, consider phone coaching with Tim or someone in his practice. It's not expensive and I think they could really help you. Or if you are a DIYer start reading books on healing after an affair and more importantly PUT IT INTO PRACTICE.
I am three years out and honestly, I rarely have a truly bad day. In fact I think the last one was in December of last year. Some days there will be a dip - but it is subtle. I will be feeling really good and a trigger will happen, and for a period of time (minutes to hours) I will feel a bit uncertain, feel a sense of foreboding/fear and then all the mental habits I have put in place kick in... and before I know it I feel really good again.
But these habits didn't just magically appear. I read probably 12 separate books about healing - from an affair, from betrayals of any kind, about the newest and most promising treatments for PTSD, etc. I went to therapy for a bit and my husband and I did some marriage counseling. I practiced meditation - both the more traditional methods and "walking" meditations in nature (my favorite kind). I practiced deep breathing and focusing on threes when triggers hit (it's a method of stilling the brain and returning focus to the present - you focus on three things you can smell, three sensations you can feel, three sounds you can hear, etc...) I journaled. I kept a gratitude journal to remind myself of all the good in my life (our brains over-emphasize the negative to try to keep us safe.) I practiced ever single method recommended for keeping yourself in the NOW. I repeated mantras in my head WHILE simultaneously doing something very physical to basically "squash" my mind's ability to ruminate. What seemed to help I kept doing, what didn't I dropped and looked for the next thing.
I took care of myself physically - exercising, eating healthy. I reconnected with my favorite hobbies. I read books that talked about resilience, perseverance and integrity. I ONLY took in uplifting material (TV, Music, Books) that reminded me of all the good in me and in life.
I honestly attacked my healing like it was my part-time JOB.
All of this is to say - it is NOT easy. I will freely admit it's the hardest thing I've ever done. But the ONLY way to stop the voices in your head and the gnawing feeling in your gut is to devote yourself to finding the methods that work for you. It is HARD, it takes practice, what works one day doesn't the next day so sometimes I'd have to go down my list of 10 different methods until I found one that worked on THAT day
But after practicing this, it began to get easier. I stopped having to carry around a list of "things to do/try" in my wallet so that when my emotions started turning sideways and I couldn't remember WHAT to do, I'd have a reminder. Instead, I found myself reflexively beginning to do one of my favorite quick "move into the now" rituals. And then months after that... I realized that somewhere along the way, I'd internalized these habits so much that I didn't even notice I was doing them. And I did them with EVERYTHING upsetting in my life.
So I found that I'd actually grown calmer and less reactive about everything. It took almost 18 months to get pretty good at it. Another year before it became so ingrained that I didn't even think about it unless a BIG trigger hit.
I have no idea it this will work for you - but it is the ONLY thing that worked for me. My mind is NEVER still and there was no way I was going to survive this (with or without my husband) if I didn't learn to tame it.
4. The other thing that works for me on a bad day is REALLY looking at my husband - not with eyes of love - but VERY CRITICAL eyes. I look at the man he is NOW. Not who he was three years ago - but the man he is today. I ask myself, "If I met this man today and I was single - would I consider him someone I'd be interested in dating/marrying?" It pulls my focus away from the things he's done in the past to who he is NOW. And frankly, over the past three years, my husband has changed a LOT. It's taken a lot of time and effort on his part just like it has on mine - but he is a far more emotionally available, kind, compassionate, HUMBLE person who recognizes that it is HIS responsibility to talk about his needs and get them met in ways that are congruent with the man he wants to be (one with integrity and honesty.)
Hopefully your wife is taking responsibility for discovering her "whys" and healing the trauma and unresolved issues that caused her to make the choices she did. if so, focus on that. Make a list of things she is changing and examples of those changes. Take this out and read it when you begin to cycle.
I hope some of this helps - Thrive