calling the boss to request they don’t work together (arguable unfair but not unknown when dealing with previous cheating)
I guess we just have really different views of what boundaries are appropriate and what aren't.
The previous cheating is between her and her husband. This is also my response to @Rosscameasdoody. You can't just take it out on random younger women.
Imo, you aren't a mother calling the school teacher to request your child doesn't sit with another child.
What you're doing here could slander and professionally jeopardise another woman, based on pure unfounded jealousy, insecurity and possessiveness. As you've said yourself, it's very much an irrational emotional trigger rather than logical certainty.
You shouldn't fuck with another woman's career or perceived professionalism – just because you dislike your own life, and because the poor woman had the bad luck of happening to breathe in the same air as your husband.
Go to therapy or get a divorce or have a family meeting or something instead. Don't try to drag unrelated women down in their careers for no reason other than spite and possessiveness.