I dunno, I think maybe it IS doable in the space of two years. Young people mature a LOT at the end of their teens, and even if they continue to be upset by their dad's behavior, they can be in a place to cope with it. Maybe they will lean more on friends. Maybe they will see a therapist regularly. It's not as if you are the ONLY person who can help them navigate the world. What if you were die? Do you think they would fall apart, never to manage life? And speaking of not knowing how long any of us has, do you really want to lose this terrific (based on what you've said about him) guy, on the chance things MIGHT not work out?
It's really a very individual decision, in the end, and one that only you can make. I'm just trying to counter your tendency to see things as black and white.
