I was in your shoes last year and went through a lot of false starts. The biggest thing you're going to have to do is detach. You are so emotionally invested in her. You watch her every move and analyze and drive yourself nuts. It's crazy, but it is kinda normal so don't get real worried about that. You need to be doing your own thing and focusing on yourself. She isn't all the way in this yet.
I wouldn't be her shoulder to cry on about the OM. I wouldn't listen to it at all personally. If you don't trust her, pull up the phone records online and you can see who she texted if it isn't Whatsapp or Snapchat or something. As for trusting her, this will take time. Don't get caught up in every little thing. Time will tell, so give it time. And start using the meantime more productively.
I also wouldn't worry about sex right now. You want sex? Go to the gym 5 days a week, accomplish chores around the house, crush it at work, save money, read and learn things, stand up tall and smile - and then you will be the most self confident guy in the world and you'll have women's attention.
So, what are YOU doing?
H 34 W 29 BD 3/12/18 Divorce Busted Spring 19
It is not things that bother us, but the stories we tell ourselves about things.