How do you trust again without going crazy?

[Startingover2]

I am having a hard night. It was actually a very hard weekend. Exh went to that wedding where he didn't want to take me. Too soon he said. Anyway I understand he was quite intoxicated and was the life of the party. He also called me at 10 to see if I can drive him to the local bar/club where the rest of the wedding party was going and drop him off. I said absolutely not. I got angry with him for even going (he went alot when we were not together and ended up all over women)but he stormed out and went anyway. The next day he tried to pretend everything was ok. I was hurt and I was up all night wondering what he was doing and who he was with.

We don't live together and yes, we are having a child now. He wants to go slow and take it "day by day". To me it sounds like he is not that committed which drives me crazy and then I start to hound him with questions and push for some security. Which then makes him get the deer in the headlights look.

We are supposedly heading in the right direction and I wasn't happy about last weekend and the wedding/bar thing but my insecurities are making me crazy. When he isn't here I go out of my mind wondering and have even done drive by's his house (hangs head). I am a 42 year old woman acting like a desperate high school kid.

He has shattered my world more than once in the past, lied to me, cheated (after separation) and led me to believe he was 'thinking' and was coming back so it's really hard to believe him now.

Do you really just say......I trust you 100%. I am not going to doubt you. I am going to believe you are completely sincere and upfront and honest. That I believe you told OW that she needs to back off and things are going to work out.....do you really do that? How do you stop checking up on them?

Thanks for the help. I really believe I have lost it.