Did you get any kind of counseling or do any self-directed healing work after the infidelities in your marriage? I fear you are still feeling the effects of PTSD from back then and this most recent situation has only exacerbated it.
Betrayal blows a hole in our self-confidence. If we do not take decisive action to rebuild ourselves with a focus on self-acceptance and self-love - it follows us from relationship to relationship thereafter coloring EVERYTHING. It doesn't allow us to see anything clearly - we could be treated well and still feel suspicious, we could be treated like crap and feel like it's what we deserve. Which is why I'd put making any decisions about your current relationship on hold unless he's being physically or emotionally abusive. Focus instead on YOU. I'd get counseling if I could... but if you can't, you will need to start reading books about healing your self-identity (I have a few favorites, if interested PM me). And every time the negative self-talk comes up (I'm overweight, I'm unattractive - STOP). Choose to talk to yourself like you would one of your kids - be encouraging, be loving, be kind. If you slide into the dark place for a bit - give yourself a break - we all do from time to time. But then lovingly, gently pull yourself back. You deserve more.
BS - Female
Married 27 years, one adult child DD May 2016 “When we are no longer able to change a situation, we are challenged to change ourselves.” - V Frankl