Can't Cum

I masturbate almost everyday, but I can never seem to orgasm. I thought it was was just because I became too sensitive to touch and that having someone else paying attention to me would help. Well my boyfriend cannot seem to fix this either. Whether he's fingering me, eating me out, or even fucking me I can never seem to orgasm. He went for almost twenty minutes the other day and I hadn't orgasmed. I felt close to the edge, but nothing had happened.

Do any of you have any tips? I'm stuck and I'm also a little embarrassed about this.
Feedback is appreciated!!