Sounds like you still love her, you are constantly looking for reasons why you should still be with her. You need to cut it off and move on. Your mind is desperate for her and it’s not right, you don’t want to move on but you need to. She isn’t yours btw, she can sleep with whoever she wants, you are just re-digging up the past and your past emotions. Don’t be scared, just move on and find someone better.