<human>: We've been going out for just short of a year, we started going out about a month after she had moved into town. (11 months later)She took a trip to LA before she started school and ran into an old fling who she says she didn't know would be in the city at all. They got drunk (in a group with other acquaintances) and she went home with him and they had sex.

When we started to get serious 10 months ago she told me that she had feelings for someone else from her hometown, it was him. She told me she cheated a week after she'd been back, she had seemed a little off for the week in between, reticent. She said that it had been eating her up inside. I asked about how she felt about her fling, Mark, now and she said she didn't know, her feelings were too mixed up with guilt.

She doesn't have many close friends here, and flirted with depression as a teenager. After she told me about what happened on her trip, I told her I needed time and left. The next night we talked very briefly, I told her I loved her and that was pretty much all we said about it. Needless to say I'm still pretty torn up about it and am still not sure what to do, and still haven't told her I feel, but when I'm away I miss her, and when I'm with her I still love her when my mind doesn't wander.
The next night I noticed she had some shallow cuts on her leg, I asked her about how she got them and she said she didn't remember how she got them and asked my why. I told her they looked self-inflicted and she admitted that she had done them, and when asked said that she did it the night she admitted what she had done and I had walked away.

She's clearly contrite, but my trust and confidence are shaken. I do love her, but I don't know if it's even possible to make it right between us again. I just want to hear any kind of external input on this, my head is just going in circles.

Can you condense the text into a few key points?
<bot>: Girlfriend warned me, cheated on me, told me, and says she still loves me and wants to stay together.