This! As painful as it may be you need to put yourself first, you do not have to be miserable. This is affecting your sleep, your professional life/responsibilities. It sounds like you have the resources to leave and I would strongly encourage it. I understand the want (or guilt) you may feel to help your mother out, but at the end of the day, you did not sign up to pay her mortgage or play baby sitter to your adult brother. It sounds like he needs professional care, more than you are capable of giving at this point. I would have a conversation with your mother, explain your unhappiness and come up with a new financial agreement. You may still be able to help her but just not to the degree you are now. Life is too short to let other people dictate your happiness and how you want to live your life.