Trouble reaching orgasm

I'm totally capable of reaching a clitoral orgasm on my own with my hands, vibrator, or shower head. It's real easy for me. But when my boyfriend tries to do it in any of those ways or his tongue I just can't. He's never made me orgasm and it's frustrating. It's not that he's doing anything wrong it's just that I can't get to that point unless I do it on my own. What's wrong with me?