@Strangedays,
Not much any of us can really say. As I see it, you have three choices. Only you can really decide which is best. You need to choose and then stick with it.
1. You can choose to stay with your husband and continue to work on the relationship. But this does mean giving up all contact with loverboy and committing to your husband. Anything less will not result in a successful relationship, after all, how often will he forgive you for re-initiating contact with the other guy.
2. You can choose the other guy. In this case, you will need to divorce hubby and concentrate all your efforts on making this new relationship work. Of course, this entails basically burning your bridges to your husband and I cannot imagine his wanting you back again if things do not work out.
3. Neither of the above. Divorce your husband and break off contact with this other guy until you figure out what you want out of life. Concentrate on you and getting your head together. You seem to think that a relationship is all love and euphoria and excitement. It is not. A relationship has its ebbs and flows. Trust me. I've been married for nearly 34 years and sometimes I want to run screaming out of the house, sometimes she wants to run screaming out of the house. Sometimes we each feel a bit less in love with each other and sometimes we cannot keep from cozying up to each other constantly. But at all times we have remained committed to each other, understanding that there are ebbs and flows. Maybe you need time to realize this also.
Good luck in whatever you decide.