Laura MATT( KUDOS) you could not have written that any better I thank God for your perspective. Laura I was in a relationship that I decided to end after ten years but throughout those years I experienced everything and more as you have described in your letter, babies born into our relationship, going thru his phone when he wasn’t around just trying to find some type of understanding that would make me see the bigger picture but all it kept doing was hurting me. I think Matt clearly explained why and how you should handle the situation but one thing I would like to add is that we as women (human beings) tend to develop resent towards those we open our heart to because we allow ourselves to deal with things we feel we shouldn’t have to but you and your friend can overcome this communication is GOLDEN when your facing issues that seem to come at different perspectives and he has to open up to you to give you the insight into his heart just as you did him but do not approach it with a “SHOULD BE” mentality better yet let him know ” THIS IS WHAT I WOULD LIKE OR EXPECT” and even putting expectations on others sometime can hinder your ability to see things from both sides because the other person may not have even known you had certain expectations for them. Sometimes we see more in a person than they see themselves. So try to forgive him but mainly forgive yourself don’t develop resentment it will hold you back from the LOVE you both were building. I hope this helps you in some way and I know I stated I ended my relationship but it was more issues outside of his baby mama drama that involved that and I don’t mind telling you more if you would like to know but overall we are still good friends and I had to realize that I went into my relationships with no boundaries and that was not his mistake but my own. You are more than a conqueror already for still sticking by him believe me he knows how special you are but try your best to open up to him and I am sure he will follow. WISH YOU BOTH EVERLASTING LOVE!!!!!!!!

Check out this link it truly blessed me and hope it can do you the same. This is how I actually found out about this Forum and website.
http://tinybuddha.com/blog/how-to-release-and-prevent-resentment-in-your-relationships/