Welcome to Psych Central, Kaisc! I hope you find some of the advice here useful.

I want to applaud you for being there for your girlfriend. I can related to what she's going through, and maybe I can help shed some light on her feelings. I've been dealing with depression for several years, now, and I'm 21 as well. Is she far away from home while she's at school? My depression was probably at one of its worsts during my freshman year simply because I was trying to adjust to being 800 miles from home. I'm also in a long distance relationship with my boyfriend for almost 2 and a half years. While it's a little different than your situation, I used to subconsciously push him away as well, even though the times when we weren't speaking were so hard that I ended up caving and going back to him. My boyfriend and I actually broke up for 6 months because my depression got so bad, he finally said "I dont think I can make you happy anymore, so I'm throwing in the towel." We're back together, but I just want to warn you that her depression is going to be extremely hard on you. Also, I agree with Christina, she sounds like she has very low self esteem. Try to take things slow with her, with lots of reassurance of your love and how you feel about her. Also give her compliments, just "You look really pretty today" or "I love the way you smile." Little things like that, to really try and cut down her self esteem barrier. Its good that you're going with her to therapy and such. I always found I'm more likely to go if theres someone going with me, whereas going by myself always seemed so much harder. I'm not sure how you should deal with her past. You should be truthful. Those girls probably didn't mean absolutely nothing to you, and you probably did enjoy those moments to some degree. By telling her that they meant nothing at all and that you didn't enjoy them probably just makes her think you're lying. You might want to say something along the lines of "You're right, I did enjoy that. But I enjoy being with you more than all of those other girls combined." Overall, just be honest and caring, and understand that she does love you, and right now she simply can't give you all the love she really wants to.

I hope this helps some. Feel free to PM me if you want to talk some more. Best wishes!
Ro