<human>: so, i'm kind of torn between options here. I've been with my boyfriend for a year and a half now, and things seemed like they were going pretty good. The only problems we really had were that he used to lie to me about getting high and drunk. Obviously, we worked through all that, and I thought that we were okay. About a week ago, I found out that he had met up with this girl a few times behind my back. I'd asked him about her several times before, and he'd denied everything. (I asked him due to people texting me, telling me that he had been cheating on me with her) I found out about it because he left his facebook up. I know it was wrong to snoop, but after being told countless times about it, I got a little suspicious. I found (in the messages) the two of them talking about meeting up, flirting, etc. He seemed to be pursuing her more than her for him. I really don't know what to do, because he met up with her months ago. That doesn't really excuse the fact of how shady he was about it, nor the fact that he lied several times, but I feel like there's no reason to leave him now because of how devoted he is to me. He swears nothing happened between them, but given his history of blatantly lying to me, I'm a little  reluctant to believe him. I can't get the image of the two of them together out of my head. Maybe i'm just feeling insecure over nothing, but I thought I should seek advice from an unbiased third party. Any help?

Give me the gist of the text in a nutshell
<bot>: boyfriend met up with other girl behind my back several times, lied, has lied about numerous other things in the past, but is now very devoted and hasn't lied in a couple months. what do?