This is the kind of thing that really makes me sad. You should NEVER do anything that makes you uncomfortable. End of story. If someone is trying to MAKE you do something sexual that you do not want to do, technically it is a kind of rape. That is sick. My suggestion is that you try to get comfortable with the situation if the idea seems good to you. If you get comfortable enough to have sex with another woman, go for it. If not, DON'T. End of story.