I'm sorry you have had to come back. But you probably know this is the best place for these types of problems.
You were here 8 years ago. What did you learn then?
What happened bewteen the two affairs? Is there something to look at that is the cause of the breakdown in the M or is your H simply not going to be faithful.
I don't mean to be harsh, but you have to take a long, hard look at what kind of man your H is.
More details would be helpful. Your age, how long M'd, any kids?