Hey - I am also a single mom of a 9 year old and 5 year old, so similar ages to yours. I agree with what a lot of the others are saying as well. However, one thing that has not been addressed, that REALLY helps me, is that I get my son to help around the house a lot. Starting at about age 7, he became a serious help. He CAN do lots of things, but he doesn't do them all, all of the time. In other words, I'm not super diligent about keeping us on a schedule with chores. But, the good news is, I know he is capable and I can call on him to do it when I need him to (when I am really low in energy). So, my son can:
take out the trash
clean up the kitchen after dinner
clean the cat litter box
vacuum
clean his bathroom
does his own laundry
and my daughter (5) can:
wipe the baseboards clean
puts her clothes away after I wash and fold them
She can probably do more, but my son and I both like her to do that while we tackle some of the other chores.
I know this doesn't really answer your question, but I can guarantee that you will get more energy back if you get them to help you more. Also, I just flat out tell them - if you help me clean, then we have more time to go and do something fun (go to a park or watch a movie or whatever. Fun doesn't have to cost a lot of money).
The other piece of advice that I can tell you is that you need to clearly draw the line where you need to. If your daughter is giving you a hard time at night, you need to draw the line and tell her what your rules/expectations are. My daughter started getting up constantly at 3 and so I put a baby gate across her door. She screamed like you would not believe when she saw it. But, I flat out told her that she and I had discussed that she cannot keep getting up at night. If she is not going to listen, then the baby gate will go across the door (the gate is actually across a hallway door, so she can go to the bathroom or get water. But, she can't come and see me.). At 4 years old, your daughter is plenty old enough to understand the rules and follow them - even if she doesn't like them. And, I told my daughter that she was more than welcome to stay awake and play in her room - as long as she didn't come and see me. Because honestly, I have about 1 hour a day, after they are in bed, for some peace and quiet. And, I NEED it. It's not a matter of wanting it, I need it. So, it's a requirement in my house.
As another woman said, try to find some parent's night outs. I used to use those quite a bit. I just really needed 3-4 hours to myself. However, now that the kids are a little older, I don't need it as much (and I don't want to spend the money on it).
Please do talk to your lawyer about the divorce decree and the insurance coverage. If he is dropping those things and he is required to pay them, then he is in violation. You should be able to get those things restored - even if he doesn't agree with what your child "needs".
Good luck!
L.