^^^ Yeah, I totally agree with the Bella thing too! I had the same reaction. I think the writers on this show can do just about anything, and do it well... except for the relationship stuff (at least most of the time).
I never saw any chemistry between Dean and Jo (although I really liked Jo, in general); I also didn't see it between Dean and the yoga girl, but I guess flings don't really count anyway; I didn't see any between Sam and Bella; and while I wasn't as hugely bothered by Dean and the Angel chick as many people were, I didn't think they were especially great together either.
On the other hand, I thought Sam and werewolf chick clicked well (the end of that one made me cry! :lol: ); Sam and the second Ruby definitely had more chemistry than Sam and the first Ruby. Oh, and I liked Sam with that girl from Provenance. She was a good match for him too. And of course I did like him with Jess, as briefly as we got to see them together. Dean seemed to mesh well with that demon chick he was trapped with in the underground crypt with- she was good, I thought. And I thought there was a total love/hate thing going on with him and Ruby #1 (albeit more hate, but still!).