TBH I think if you're constantly going back and forth about it in your mind to the point where you want to write it out on an online forum, it is a sign that you're not at peace with it. My experience with this sort of thing is that it is like an orange/yellow flag (not quite red, but certainly not green. It's enough to make you slow down). You can stop or you can move on, but understand if you do, you'll be living for atleast the next couple of years, if not the rest of your lives together, with that decision.
You keep saying she shares your morales, but you might want to sit and really consider whether you're trying to convince yourself of this. For me, a person having more than fifteen sexual partners in the past does not matter and I am not even someone who engages in casual sex, I just don't hold it to such high regard or was not brought up to believe that it is a sacred act. But you might be different and that's okay. Your peace of mind is important in general and in your relationships. She sounds like a great person and also deserving of someone who can accept her wholeheartedly. Hope you can come to a decision which results in peace for you both in the long run.