Heather, He sees that you and the girls are moving on w/your lives and it's all good. He is now just realizing that he's no longer a part of that. He's wants to be in your lives. He doesn't realize that divorce means that you are now free to move on w/someone else.
So sad for him to just now realize what he had was the best part of his life and he tossed it away. Please, please do not allow him to reel you back into his drama. Stay the course and live your life to the fullest. Okay?
Sit quietly, the answers will reveal themselves when you least expect them to. The past is gone, the present is a gift and you need to focus on today, allow the future to reveal itself when it is ready.