Oh Boo! Can't tell you how sorry I am that this has happened. I feel just sick for you. This just sucks!
I agree with the general consensus here, you don't have to, and shouldn't keep secrets for him. For your own well being and sanity talk to someone. Tell your closest friends or a therapist, but you must vent.
He can blame it on the booze all he wants, but there is absolutely NO good excuse for bad behavior. NONE! The lies and the deceit are as bad as the act itself.
Hang in there sweetie, you are strong and you'll make it through this.