C.O.
I'm trying to grasp it all...
You sound like you need some serious counseling...I think I mentioned before that you shouldn't be dating for at least a year so that you can figure out who you are...and today with this? you sound even more lost....
You need to figure out what it is you want...if you still have love for your ex then it's possible to forgive him and who knows - he might have grown up...I don't know...
I've not walked in your shoes....but from this? you need some serious counseling to get you where you need to be...you are overwhelmed with questions and guilt...
Maybe a good relationship with God will help you as well? Try talking to a pastor, priest or rabbi to get some inner healing going on...
HUGS...and prayers