I've been struggling with this for about 2 years. A man who I've had an on/off thing with (although I haven't seen him since Christmas).
He isn't my type intellectually and he isn't a nice person. I think he enjoys doing this push me/pull me thing with me. At times he acts as though he's obsessed with me, interchanged with rudeness and the silent treatment which he'll suddenly apologise for 2 days later with some stupid explanation like 'sorry, I was in the wrong'. I find it stressful trying to understand what I find compelling about him when he is so unpleasant. He's never had a girlfriend and women seem to avoid him. I feel as though he must have done something to hook me though as I was not bowled over the first time of meeting.
I am not as obsessed as I once was but I feel this should have been out of my system long ago. I do so well blocking/ignoring him for weeks and then slip. A friend read some of his messages to me and said he sounds disordered.
I think it is fading but it irritates me that I can never cut contact once and for all.