Nails - given what you have gone through, with little actual support, and plenty of obstacles and hostility, it's hardly surprising that you are feeling this low after your mum's passing.
No matter how much we accept that a death is coming, it is still a huge emotional shock, and emotions are the part you have no control over.
I am pleased to read that the practical aspects that keep you manacled to your family are reaching their end, and you will be free to be away from them and their nonsense, and grieve properly for your mum, and move on with your life as she would want for you.
Toxic families are best treated like toxic anything else - cut them out and forget about them.
You have done so well to get through all this, and I know you have the personal strength to get through this last part, hard as it is, and emerge the other side without all the stress and strain you have coped with for so long.
It's very nearly time to put down the load, have a rest, then get up and walk on, feeling lighter, into a better future, and I know you can get there - all your friends on here know that as well.
Sleep well, tomorrow is another day closer to the rest and peace of mind you do deserve - you have definitely earned it many times over.