Would it be rape if I communicate i want to have sex, and then she has sex with me because she would rather have sex than "explain" why she doesn't want to have sex with me.

No. It would be bad sex. When you're having sex with someone, you have a responsibility to that person (regardless of gender) to make sure they're happy with what's going on. So if the person you're with isn't smiling, isn't kissing you enthusiastically, and you're initiating everything (you're taking off both your clothes, you're doing all the groping etc.) it might be worth just asking, "Are you OK? We don't have to go any further if you don't want to." Not to avoid a date rape accusation, but just to make sure the other person is totally happy with what's happening.