I've had this problem for a while now.

I start feeling attraction with a certain girl, so I go, talk to her, we build up a pretty solid relationship, but after some time I start acting really cold and far. I start feeling like she bores the shit out of me (that's probably true).

Every time I tried to start a relationship with a girl after about a month or so I start feeling like this, it's a problem to me, I really don't know what is the cause to this, I feel like I have better things to do than staying with girls, the feeling between me and the girl vanishes beyond physical attraction and I start giving dry replies to her when she tries to talk to me.

I don't know if you've ever been in this kind of situation, but it's really stressful, If so, how did you overcome this? I can't live with it anymore