Mandy, I'm so sorry to read about your son's injuries. I do hope he's doing better. That was a nasty spill he took.
Yes, the wifey and your X are like to spoiled brats wanting their way. I've seen that same behavior in my X as well. When they want something, they are all way too nice, but when they don't get their way, they "punish" those who do not give in.
They've not grown up yet. Will they ever? Time will tell. In the meantime, take care of yourself and your son. He's a very smart young man and can see the writing on the wall when it comes to his father.
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.