Oh you poor love. Your posts have made me cry. I can feel your pain.
Just take some deep breaths.
This is a normal part of the grieving process. You've been running on overdrive and now your body can't do that anymore, so is forcing you to slow down. Listen to your body.
I know you want a new kitchen and the kids rooms decorated but they really don't need toto be done. You need to pare down to essentials.
See the lawyer and pass everything over to them. Stop letting your arsehole ex bully you and just tell him you are too sick to do anything and to contact the lawyer.
Just do the bare minimum. Feed the kids, cuddle, watch movies, go for a walk everyday. It will all sort itself out eventually. Xx