Couples counseling, if you want to pursue the marriage.

Individual counseling even if you don't want to pursue the marriage. This will help you decide if you want to work on the marriage. It will also likely help you work on yourself. It's quite easy to say that he's the bad guy here, that he's looking to cheat, that he's lied before...and all that is very legit to be concerned about. But there are two people, and rarely, if ever, in a marriage are the problems solely on one person. Individual (and couples) counseling will help you work on yourself. And that's all you can work on, really. You cannot control what other people do. You can only control what you do.

Best wishes for a resolution that furthers your happiness in life.
-tulip