I wasn't directing it at you, was for the people who can't believe some people just have normal sex.
I know you've probably heard it all, but have you tried online dating? It sounds dumb, but you really have nothing to loose but a bit of time. My buddy was pretty down for a while after breaking up with a serious girlfriend. He resisted the online shit for a while, but when he finally caved, he ended up meeting a few girls and going on real dates. He is still dating one of them over a year later. Not saying he met his sole mate, but at least he's not alone, and has probably learned more about what qualities he wants or doesn't want in a partner.
I think late 20s is a tough age to be single, all your buddies are getting married, having kids and or getting more serious about their career.