Don't know what to do

My boyfriend and I have been together for 2 years. He's been separated from his baby mama (wife legally still) for about 5 years. Their daughter is 8 years old. The reasoning I guess is that he doesn't have the money which his sister has offered to pay. And he likes that he can see his daughter whenever he can. Do I give him an ultimatum he files this month or I leave? Or do I wait it out another year hoping he'll do it?