So frustrated!!!

Okay, so I don't mean to be a bitch, but I have to get this off my chest. My boyfriend and I have been together for 2 years, and recently lost our virginities to each other in December. When he's horny, he's all for it. He's never been selfish with oral, or anything. He'll make sure I finish, even if he doesn't. But when he's not in the mood for it, he's practically useless sex wise. He used to have a high sex drive, like me. But ever since we had sex for the first time, it went down a lot. I keep things interesting (we don't do the same positions over and over, keep times spontaneous) but his interest level is strictly down to when he's wanting it. Am I being selfish, or crazy? We have sex maybe once every 2 weeks, but he wants blowjobs all the time. I'm stuck.