MOM 21 SON, you are doing the right thing by taking care of your family, your dh and son. Everyone else is extended family, and the needs of your nuclear family come first.
my dh had always liked my mother, but the line was that we would never live together. When she could not walk, and needed 24/7 assistance, she and I and my dh agreed it was best for her to be in a facility with trained people . She picked her nursing home, and it is an excellent facility. If we all had lived together we would have driven each other completely batty.
And my mom is reasonable and we generally like each other!
Do enjoy the silence from your brother!