Your statement about "I know that once she goes she'll run and won't come back is mindreading. You don't know that. You do not have a crystal ball.
All you can do is improve yourself, be the best man and father you can be and everything else will fall into place. Isn't that the advice this whole Board gives to one another? Easy to say, hard to follow I know.
I am taking the long view approach myself. If my WW wants to work on the marriage that is up to her. If not, I am prepared to carry on and be strong for myself and my children.