help!

So ive been with my boyfriend for years now, and ive gotten him off, probably close to a hundred times already. But no matter how much we mess around, how much sexy time we devote to me, how much he does for me, i cannot get off. I cant do it. I never even feel close, i also cant get myself off using my hands, literally the only way i can is by laying under running water or using a vibrator. It makes me so, so sad. Does anyone have any special techniques? I know that often girls cant orgasm through actual sex until theyre older but for the most part they can still get themselves off without any toys. :( someone help.