True, You know what I would do? I'd delete the message and go on my merry way. You are divorced and you do not need to be bothered w/this nonsense any longer. He needs to understand that you've moved on. Do not get sucked into his drama. You need the money as well to live on.
Delete the message.
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.