I like to within reason. My H is a control freak, so I am standing up to him about that stuff. Don't know how many times now I've told him "the Ls will work it out" when he tries to manipulate me into something (and I don't let him anymore).
I don't have your exact situation, but have an H that just took my D8 and S14 out on a date with the OW on Friday night!!!! I plan on saying nothing to my H (figure it's not my job to teach him morality even if he was able to learn it which he probably isn't), but just talk to my L and the kids' C and let them handle it (and do whatever they direct me to do re: the legal/psych. wellbeing of the kids).
I think in most cases I've taken or tried to take the high road, and my H chooses the low road. What will happen? I know that I am already probably feeling better about myself and sleeping better than he is. I think in the long-run I will have a happier, better life. But maybe I'm delusional, so you might not want to hear my advice anyway! Karen