I obsess because in the therapeutic relationship I feel I am desperately looking for something. What exactly I am looking for or how I am going to find it, I am not sure. But its something very deep and probably rooted in childhood.

Its like when you are trying to solve some problem and you just can't let go of it or give up.
Or like when you love someone, and they don't love you, and you can't bring yourself to believe it.