Sort of reminds me of a scene in Walking Dead.
Governor: Take off your shirt.
Governor: Take off your shirt or I'll bring you Glen's (severed) hand.
Maggie immediately removes her shirt.
Of course she 'made a choice.' Of course she could have continued to refuse. But she was obviously coerced into it by the threat of something bad happening if she didn't.
To face the loss of marriage, income, home, time with children...these, to most parents and married people, are 'something bad happening.' Of course we CAN just hop off the ship and go. But we realize that our presence on the ship is important to us and very important to our children. If we're decent people, we consider the impact on everyone around us, and most parents will put up with an awful lot before they'll take a step (divorce, separation) they know will harm their children.
To claim that choosing Lousy Choice A over Lousier Choice B is not coercion is simply wrong.