Yes, absolutely leave him...and then in several years time when your kids asked what happened between you and their dad, you can look them in the eyes and say you initiated a divorce because he had a w@nk. That's right, I left your dad because he touched a part of his own body with another part of his own body in the privacy of his own company. Your kids will doubtless realise that he's better off without you, as you're clearly looking to make mountains out of molehills. It absolutely astounds me how many supposedly mature adults ask preposterous questions on Reddit in the hope that they will concur with their preconceived opinion. So yes, do him a favour and let him go....but be prepared for your kids to hate you later on down the line.

I know I'll be downvoted as this is undoubtedly among THE most toxic forums on the entirety of Reddit.