Tip: sexually active men are never "friends" with women they like. Some might pretend to be because they think it's a way in but there is no such thing as a "friendship" between two people if one of them wants to fuck the other. Believe me, I've never been "friends" with a beautiful woman in my life and never will be. Essentially your girl is trying to dump you in as gentle a way as possible. Forget it and move on. If you pine for her and plan of "winning her back" you'll be entering loser territory. Move on it's over. Plenty of other women out there.
That's actually similar to the situation I was in not long ago; nursed my mother to death, maimed myself shortly after and was stuck in a wheelchair for months. When I hit rock bottom I always seem to spring back and get stronger. Honestly, nearly killing myself was the best thing that ever happened to me in a way. I feel great. Better than I have ever felt in my life before to be honest.
Everyone has been through similar stuff. Especially when they were young. I was a different person in my early 20's. I didn't really become a man till my late twenties which was not so long ago. Just forget about your ex. You're infatuated with her now but in a year's time you'll have forgotten all about it. You won't even remember what she looks like. So move on.