The thing is
@Eirawen and I know I've said this before, the TV work doesn't have to dry up, yes eventually it will have run its course and her audience will move on, but she absolutely could go it alone without him. He adds nothing to the show apart from the obvious when people scratch their heads at his behaviour. I'm not a Sam fan I watch because I'm curious how it will pan out but I think there would be a market for just her and the kiddos.
Sadly I think he would put a stop to her having the children on the show if they did separate, say its damaging them and he was never in favour of it. I also think he'd go for full custody. I think Sam might know this deep down.