After spending a half-decade wearing 4" heels and a sprayed-on catsuit onscreen for Star Trek: Voyager and offscreen shacking up with the Executive Producer of said show, I think the former Ms. Ryan has probably developed a uniquely thick skin towards these sorts of things.
I see your point about Ms. Ryan's onscreen personas. I don't think her skin is thick enough to put up with her son being embarassed. She also fought to keep the records sealed.
I do have a problem with her shacking up with that man, but if her marriage was the way she portrayed it, she instinctively sought a male that would "protect her". Of course it's wrong, but so is psychological abuse. Just because she's a well known actress doesn't make her any less human, and the child any less vulnerable.