If she is motivated by fear, she won’t understand how you love. If she doesn’t love as you do, she won’t understand your efforts to help others. If she doesn’t support your efforts to make the world a better place, you cannot spend your life with her. If you cannot spend your life with her, it would be unwise to sleep with her. If you won’t sleep with her, she won’t want to be with you. Sex is means to intimacy. There is no sex without risk of hurting someone else or yourself. To risk hurting someone else in pursuit of personal gain is selfish. Sex with one who doesn’t love the way you love may require you to give up on love your way.
But this society is asleep. The Id rules us. The presence of this understanding is reason to let fear motivate. To not let fear motivate us is irrational. And yet, you do not. You do not let fear motivate you because this is what love means to you. Because maybe it is rational if we aren’t afraid of being hurt, if, instead, we aim to reduce the hurt of others.