There is no excuse for having an affair. Sexual, emotional, whatever. That was a mistake on your part.
That being said. Is you marriage really worth saving? I have grown daughters and I would council them that alcohol abuse, emotional abuse, addiction to pornography are all deal breakers. Maybe a separation is in order such that your husband can decide where his priorities are: family or alcohol & porno.
I would suggest contrition for your failings (affair) but don't let that be a reason to settle for a poor marriage.
