You don’t need to be anything for your family, from what you’ve said they aren’t exactly supportive towards you.
You’re a wonderful mum to R, you consistently go above and beyond and exhaust the means and resources you have to try and make things better for him. That is incredible and more than most of us could do. Even though it’s exhausting and often debilitating, you still attend each and every meeting with his school because even when you have nearly nothing left to give, you still fight for him. He might not get it now, but he’ll appreciate it when he’s older.
Is there any way you could use the rainy day fund to stay in an air b&b or something close by for a few days? Xx