I'm also one of these mostly perpetually single people (although, if I remember correctly, you have a weird/tenuous connection with my first gf), but there's one thing that I've found to be true, once you're in a relationship, more possibilities open up. I don't get it myself, but in my recent persuit of Cute Redhead Nerdgirl (someone from Toastmasters) I found that once I thought I might get to the point of asking her out (although I've not seen her since *grumble*) I found myself getting attention from two separate people that very weekend.

Unfortunately, it's analogous to the work experience paradox ("How can I get experience in the field if all employers want experience in the field?") but I think it's about having some signal of "I'm attractive to somebody" that kickstarts everyone else into looking at you with a view of "Oh, she's attractive to somebody".

Anyway, I know where you're coming from... good luck.