Orgasm from crunches ?

I really enjoy orgasming. The problem is I can only usually achieve them while doing crunches. Yes, stomach crunches. Some types do it better than others, but nearly all kinds, if I do them long enough, will do the trick.

First, I would like to know if anyone else has had a similar experience. I'm 25, work out a decent amount, and this has been happening for awhile. I used to find it quite novel and felt like I was blessed with a body that would give me a real incentive to keep my stomach flat But more recently it has been frustrating me as it's beginning to affect my sex life.

I haven't had much sex in my life until recently, and now I'm dating someone that I really like and would really like to enjoy sex with. The problem is that it's nearly impossible for me to orgasm without doing crunches. I don't know if it's the way my legs are positioned while I'm doing them or the way my clothes are touching down there, but I'm clearly made differently than other women! I have masturbated successfully by just touching myself but it takes me a REALLY long time and I feel like I could never get my partner to replicate the strokes and speed needed to get me to orgasm. And that's just by touching me. When it comes to sex, it feels OK but not great, and I feel like I'd never be able to orgasm that way. I also feel like it's harder for me to get myself to orgasm if say, I did crunches, and orgasmed that day or the day before.

Am I all alone here or is there someone else that might have similar anatomy to me and could offer some tips on what might be pleasurable? Sorry for the weird post, I just feel like it's time that I need to tell someone this and see if there's any hope for me. Thanks so much in advance for your help.