I absolutely agree with what NOPs said, use protection anytime you have sex with him....and postpone having children until this is worked out COMPLETELY.
The sad fact is your H has a history of cheating, multiple times....the probability is high that he's doing it again. I find it interesting that your H claims he has talked to you...but you aren't paying enough attention to see it? That's double talk hon.
Backoff of him....stop pushing. Right now, you are appearing really needy to him. He's most likely got someone else (sorry to say that) you appearing needy is going to drive him to her. I'd definitely start checking up on him though to find out for sure. Check cell phones, check bank accounts, credit card statements....if you don't have access to these things, get it....it would be too easy for him to hide things from you if you don't have access.
Do what we call GAL (Get A Life) as well. Do things without him, invite him if you'd like...but do them anyway. Join a club, join a gym, dance class....go back to school...whatever, but do some stuff just for YOU. This is going to do a couple of things. #1 Start making you feel better about yourself, & #2 Start making you appear less needy of him and therefore more attractive.
I wish I had more time right now, but I know some of the other ladies will chime in here and give you some great advice too.
