I think there is a thread on this in relationships.

I met DH through mutual friends. I had known him a while before I asked him out, as he played in a band, and I had seen them a few times. My housemate (one of the mutual firends) bugged me for a ges to break up with my then boyfriend and go out with DH instead.
I waited and eventually we did break up.

DH's housemate asked me out to the movies, and I (naively) thought he meant with a group....so then I had to tell him that whilst I did think he was a great guy, I kinda had the hots for his housemate.

He was OK to start with, but I think me being there all the time wore thin cos after a while DH got kicked out of the house, and the band they were both in (which DH started mind you!!)