I think it was important for you to do what you did today. You don't live in a fantasy world, and you don't want to. So seeing all the things you saw today was helpful in describing the reality that you are dealing with.
Read Jack's story again, carefully. He did something that you are reluctant to do. He showed his wife that he was willing to live without her. It was a risk. But I don't think he did it as a risk. He did it because he believed that he would be fine without her. And he was willing to go it alone.
You are enabling your wife in her fantasy or vacation life. You are giving her money. You are bailing SS out at school. You are helping with his homework. You are there to support her so her new life doesn't turn into the same kind of difficult unpleasant daily drag that her old life did. Why?
I think SS is the real problem. She can't handle him. She's decided you can't handle him. For now, he is responding to OM. So he is a godsend. Until SS gives OM the same trouble he gives both of you, OM will look like that guy on the white horse she is waiting for.
Don't help her. Let her sink or swim in the new life.