Recently my girlfriend and I have become more sexually active. We've agreed not to have intercourse, but to do everything else. Along with our discussions came the issue of masturbation. We both do it, but she never achieves orgasm through it. She hates that I do it, although I've explained it is natural and healthy for guys and does not affect anything we do and does not make her less important. I do not know really how to approach the issue to make her feel better.

Basically, my problem is that I cannot seem to cum during oral sex or intercourse. If she uses her hand then I reach orgasm within an acceptable space of time. However, when having sex or receiving oral sex, the feelings build up but never quite reach the point of orgasm. Is this normal? Is there anything I can do?

Is it masturbation healthy or does it cause some diseases?

I've been sexually active for a while now (I'm 20, sexually active for almost four years now) and have no interest in masturbation. All my girlfriends rave about it. I do it sometimes, mostly when my boyfriend and I have phone sex. But honestly, it really doesn't do anything for me. Plus, when I do masturbate, I can never achieve the type of orgasm I do when my boyfriend touches me. It's never as intense. My boyfriend's leaving for college again soon, and I think I'm going to go crazy without him being here to pleasure me. Any suggestions as to toot my own horn?