My husband's best friend drunkenly tried to get with me

Hello beautiful people. So I need a bit of advice. Recently my husband's friends were over and we had been drinking. All but 1 person was drunk (myself included) and when the beer ran out my husband and the sober friend left to get more. While they were gone it was just me and his best friend. His best friend started hitting on me and grabbing my breasts. I did stop him and he respected my decision to not do anything. I knew this man years before I had even met my husband and not once has he ever been like this. He is married and had a beautiful baby boy with his wife this year. I'm thinking that maybe he is having bedroom problems with his wife and maybe just was acting out. So my question is do I tell my husband and possibly ruin his friendship and maybe even a marriage by saying something? Or do I just keep it a secret and write the behavior off as just to much drink creating a bad situation provided it never happens again?

Edit: for the person who commented that I would be down for something happening, wtf? If i wanted something to happen I clearly had an opportunity and very much didn't expect or want the opportunity to even be there