I don't want to help my ex wife out more monetarily or with extra time now that our son has a time consuming medical condition
Was there more that you used to do?
Yes, I was paying more monetarily and with extra time on her. Now she's going to pay the penalty!
You can feel tired and upset about this. But you're both responsible for caring for your child, no excuses.
I didn't ask for this.
You did when you had the child though. I think that it is expected that both parents will take care of their kids.