I don't really know what attracts me to certain personalities in certain series. With Supernatural, I was immedietly drawn to Dean. It was instant. The same came with Rodney. But strangely, when I first started watching SGA, I really thought that I would be drawn to John, but nope, McKay was the one that captivated my attention, which was weird because Jack was the one in SG1, I guess I go for the wounded hero type. BTW, I found this wonderful story on the boys of Supernatural that is so good I just have to share it with all. It is well written, save for a few errors here and there, but the story line and the personification of both characters is flawless.
I know how you feel!
Here's the link, I know you'll love it:
http://www.fanfiction.net/s/2787883/1/