Posrschelvr
give this some time to think it out. This is not the time to make any rash decisions. Talk openly w/ him. There is a reason he told you and you need to understand why he did.
This does not excuse the adultery thing, but this is not the end of the world. Sometimes this opens avenues of better communications and, sometimes, could actually make for a healthier relationship.
Men are vulnerable and stupid when it comes to women's prowlness. Obviously, these ladies came on to him knowing damn full well he was married. If you have the opportunity, ask them, in front of your husband, just what the f**k their intent was? Are they so sorry that they can't find anyone else???? Do they think it was okay to possibly destroy a marriage? Obviously, you need to get rid of your "friends" before you consider leaving your husband.
I'm sorry you have to experience this, but wish you luck....