Nothing. WORDS MEAN THINGS. We all know how he really feels. I truly don't think there's anything he can do that won't make it worse.
So what you're saying is, no apology or amends would be acceptable to you? Wow. Are you that unwilling to forgive the people you actually know, or is it just strangers?
I knew of a man who during a blackout sexually assaulted his mother. Do you think he harbored these feelings for his mother sober? I think not.
I understand you may never feel the same about Mel but if he is truly sorry for what he has done give him the chance to prove it.