<human>: Can you condense the text into three sentences or less?

My girlfriend of over a year (we also dated in high school for nine months, with over a year in between where we dated other people) just broke up with me.  She is 19, I am 20.  She says she still loves me, but that she wants to instead be with a friend I've known since I was in primary school with him.

This is completely out of character for her.  She has never violated my trust before, then suddenly she tells me that she's been kissing my friend and wants to be with him instead.  For the last year I have been trying to be extremely supportive and good to her, as she is currently suffering from depression, is failing at uni, and just started a course of anti-depressants in the past couple of months.

I have never violated her trust or done anything wrong to her that I can think of whatsoever.  She has never done wrong by me in this relationship, and she makes me happy when ever I talk to her or when ever she is around.  I don't know why she has done this, it isn't consistent with her prior actions in the slightest.  She has been the best part of my life and I would have done anything for her.

I am lacking in friends, and this break up has left me without two of my best friends and the person I wanted to spend the rest of my life with.  I don't know how to cope with this.  I feel betrayed and hurt.  The fact that they have done this to me makes me feel like I am worthless.  Days ago I worshiped her, now she has treated me like we had nothing, discarding someone she has a year of intimacy with for someone she has never been with.  I don't know what I want to do with the rest of my life now.
<bot>: Girlfriend dumps me for some asshole who happened to be one of my best friends.  Don't know what to do with my life, or to continue it at all.