compromise sex

I'm asexual, but my partner wants to have sex: should I just compromise and do it?

Nehremi
asks:
I'm Asexual and currently engaged in a romantic relationship with a woman. She really wants to have sex, I'm not really into it. We've done other things I really like, like making out and heaving petting. How do I tell her that I don't want to sleep with her without making her feel inferior, undesirable and bad about herself? I'm scared to hurt her. Should I just compromise and sleep with her?...