I can relate to the way you are feeling, and can say that it is PERFECTLY normal and expected to feel this way. While it totally sucks, you are working through some serious trauma (emotional), and there is nothing wrong with how you feel.
This is the challenge in R: your mind, heart, soul, etc., is trying to protect you, and telling you to get away from the source of your trauma - it's biological, it's natural. But you are forcing yourself to go against all your instincts to stay with this source of trauma, and as a result, you are having to process and reverse a LOT of pain and hurt within yourself that he 100% caused for you.
For some people, this is simply too much, and they feel they can find true happiness and safety and trust with another partner, so they move on. In fact, that is MUCH more common (statistically) than true, successful R. And for other people, they have the willpower, strength, drive and determination to try to take a very shitty situation and turn it into something that could possibly be better than anything they've ever had. It's a shit ton of work - don't get me wrong. And it isn't for the weak of heart, that I can say for sure.
Only you can decide what is right for you. Your WH gets NO say in that. He lost his right to decide things for you when he chose to step out side his marriage, violate his vows, and violate you as a person. Don't feel pressured to do "what's right for him", do what's right for YOU! Only time will tell what you feel in your heart is what's right for you, but rest assured, you will!