I had an epic makeout session with my best friend
Is there a reason you decided to make out with her?
No, she just happened to be there at that moment.
It is risky to make out with your best friend. You would be putting your friendship at risk later on.
I really don't see the problem. I never take advantage of her.
I can understand that you don't see the problem right now, but when you mix feelings with the situation it gets out of control. It's not a good idea to put a friendship at risk. If you do that then it will never be the same.