Only you can know what you did before. Still, the matter is that you're hurting with what happened.

As you keep telling yourself and us, it happened last year, AND this year is about to end. What's stopping you for forgiveness?

If you can see that he's making an effort, what can be stopping you now? I know it's a tough situation, but only you can decide if you really want to forgive him or get done with it.

By the way, no, it's not "normal to be cheated on". It can happen to anyone, but it shouldn't happen.

Happy hollydays, cheers!