I have a girl friend who does that to her friend. I keep telling he that this is wrong but she doesn't listen. The reason why is simple, this is the perfect relationship for a woman; he is a friend who does everything for her except having sex. Moat women are different act this way, they look for support in men so once they get it they never let it go, they don't care if is from a friend or a boyfriend, whoever gives it they'll take it. The problem is that this is egoistic and can potentially hurt somebody else's feelings, in this case yours.
I would say that you take some space to breath and think about what you are really getting our of this relationship and if it's not what you expect just forgive here for being selfish and rebuild your life. Go out and meet new friends, if you are a good guy you'll find a good girl for sure.
That's exactly what my friend's friend did and now she just realized that she kind of love the guy. Once they miss you they start falling apart