You need to say these things to her.
You need to apologize to here. Be specific about what you are apologizing for and do NOT use the word 'if'. You KNOW what you did, be a man and accept responsibility.
YOU need counseling...for the gambling, p0rn and anger management. Make an appointment ASAP.
Get rid of the premium movie channels and put a lock on anything rate "R". Have your wife enter the pin.
If you want to save your marriage...you need to 'walk the walk' and 'talk the talk'. You can ask for another chance, but be prepared for her to NOT give on. Let her know that you are seeking professional help for gambling, p0rn and anger management.
If you air your dirty linen in public, expect people to comment on the skid marks!