I know what your going through. My husband is so charming , kind, funny etc. when he needs to be that everyone loves him.
My AH loves crack and after a two month jail stint. I eventually reconciled and stayed by his side. He was out of jail a week and about to go off to rehab when he relapsed and I kicked him out for good.
And let me tell you there was a line it seemed of women and friends just waiting to be able to enable my husband. I posted on this subject before. It is very disheartening to put out firm boundaries just to have them find 1000 enablers with not one boundary in place.
I also had to endure seeing one of the women my husband cheated on me with (he denies) and it haunted me for a while. Cheating for me is a absolute deal breaker. I'm sorry he cheated on you so much. That is unacceptable and you definitely deserve so much better. I do not believe just because you are an addict you cheat. My dad has been a alcoholic my whole life, but he is not a cheater. He is a one woman man. Using isn't an excuse to cheat.
It sounds like you have a lot going for you. Focus on your exciting future that awaits you. You just graduated that's awesome!
What happens to our thinking and emotions when we are with some one in active addiction is tragic. Our thinking becomes distorted. You did the right thing. Don't feel guilty. It sounds like he had it a long time coming. His addiction is not your problem to sort out.
Save yourself
Safeguard your future