I'm sorry you were used like that.
You have already did a good thing by blocking him and cutting contacts with him.

Now that you've dealt with that, I think you should re-think the relationship you have with your husband. Since you basically cheated on him, perhaps your marriage isn't going as well as you thought. I'm not going to say to confess everything to your husband because that's your choice. But I definitely think you need to adress these issues if you want to put all of this behind you.