Try set yourself small tasks every day. Achieving them will result in motivation. Start small - take little steps and go easy on yourself. Ensure you get enough sleep and are eating well.
Thinking of you - btw. I know you are relying on your son for support, and he is not meeting your needs; just want to let you know that we are here for you too. I know it's a bunch of virtual friends, but our feelings and support for each other are very real. My T actually put PC on her notes as a part of my support-system; because in real-life I have a very limited support system