I've been with a girl I love for about 3 years off and on. She's my first girlfriend in any fashion and I know she loves me as much as I love her. The problem is that she's flirty with other guys and doesn't realize when she's gone too far. When we first started dating she would make sexual jokes with a friend of mine and they would hang out alone on numerous occasions. I asked her to stop hanging out with him alone and she refused and it turned into a fight which caused us to break up. Two weeks later I apologized and we got back together. In the time we were broken up she made out with this guy a few times and spent a night at his house from what I could gather. It hurt me but I wasn't about to let it get in the way of my feelings for her.
We stuck it out until we graduated high school and the first week of college she broke up with me because she felt it would be too hard on the relationship (we were going to different colleges). She would text me off and on saying she missed me and wanted to see me and eventually I caved in and had to see her. After much pain and effort, my friends did everything in their power to prevent this from happening mind you, we became a couple again. Two days later she broke down and told me she had slept with two other guys when we were apart. I saw this coming, forgave her, never told anyone and never talked about it again. I was afraid of having to live that down if anyone else found out. I've been spending the last 2 years defending her for the first thing. If it's not known yet, I love this girl, despite her flaws. We all have them. My question is this: Is their any hope for this to be a healthy relationship? I'm hurting inside and I feel like she's giving herself away to everyone but me. I love this girl sooo much!! Is it worth the pain? Can I trust ever her again?
Thanks again for any advice