<human>: Can you summarize the given text in a few sentences?

My bf, now ex, was dating for two years. For the longest time he had me and everybody else that he was the faithful type. I also had some sort of feeling that something wasn't right. When he left his phone at my house, I couldn't help but to look through it. turns out he's been lying to me all these years constantly talking and flirting with other girls, creating all these online dating site accounts, asking them for numbers, snapchats, skype, kik, everything.

He never physically did anything with them, so he says, but I don't believe him. Now he's completely hating himself and is trying to change, again, and wants me to get back with him. If he's really serious about changing this time, a part of me wants to get back with him, but another part of me hates him.
<bot>: boyfriend of two years was never faithful to me. Claims he's going to change, but I dont know what to do.