My girlfriend and I have been dating for over a year, we have a 4 month old baby together and we get along amazing (most days) but I have a small problem with something.. I have caught her in lies concerning her ex. For the longest time she claimed they didn't talk, and then I began checking her texts from time to time (which I know now I shouldn't have) and she frequently talks to him (atleast every day) so I confronted her which came to a huge argument. I let it go and told her I didn't care (when I really do) and carried on. I just asked that she not see him because that would make me very uncomfortable. She claims that they were good friends long before they dated, and they dated for over a year and broke up and now are friends again. So I let it go for some time and then curiosity hit me and I checked again only to find that she went to his house WITH our 3 month old at the time. She claimed she went there only because she was with a friend who needed to stop to get clothes (her boyfriend lives with him). I was still extremely uncomfortable and felt as though she probably knew all along. She constantly still hides it from me, even though I asked her not to. I work all day, I leave at 8am and don't get home until after 7pm and it makes me uneasy not knowing what she is doing all day, or if he's ever been to my house. I want to trust her, because I love her more than anything but I don't know what to do. I try not to think about it but it never leaves my mind. If I ever bring it up, she gets EXTREMELY defensive and it always starts a fight. I told her I'd never be controlling so long as we had trust but I feel with her constantly hiding things from me that its slipping away. I just want her to be upfront with me and tell me why he's so important in her life that they need to text all day long every single day. We only spend about 3-4 hours together a night and I find she has her cell stuck in her face for atleast half of it in which I'm 100% sure she's talking to him and ignoring me. I want nothing more than a trustful, loyal relationship with this girl of whom I someday picture myself marrying. Can someone just give me some advice on how to block the thoughts or something, maybe help my uneasy mind and put this all behind me!
Also, the reason I checked her phone in the first place is because of MY ex. I got a hint from a friend at the time that she was seeing her ex, so I checked her phone one day only to find she had been cheating on me all along. My ex told me she saw him once a month to give him money for a shared cell contract they had which was true but she left a LOT of things out... I have never been the same since and I feel like its really affecting me now. I just want to stop thinking about it! Advice, PLEASE!