I am really happy for you. This is so painful for you and your kids, but you have grown in so many ways. You've learned some valuable lessons out of all of this, and you will have a richer, better future as a result. No one can say exactly what that future looks like, but you will have your new frame of reference on life to take you the rest of the way. I saw myself in many of your posts (but not the part about my in laws! I've had no contact with them and am sure I'm enemy number one; they never really liked me from the start).
You have reached a depth of understanding that I believe few people in this life know. It's what the ancient Greeks wrote about centuries ago--through our suffering we may finally reach a point of greater wisdom, provided we are paying attention. You've been paying attention when a lot of people are still sleepwalking. Yes, it's easy for you and me to wonder why we didn't do this before, why it took so long, why it took so much pain, etc.
In the end, such questions are pointless. Our lives unfolded as they did. In the past, we acted with the highest level of consciousness we had at the time. We've moved to a deeper level of consciousness now, and so our task is to implement that in our new lives. The tragedy would be in reverting back to old ways knowing what we do now.