Moving on away from the past – how to stop feeling sadmess and guilt

What is a new thought that I can think regarding my son who has mental illness? He is 23 years old and lives with me… he has been diagnosed with schizophrenia. He has no friends, and doesn’t leave the house except to get his daily alcohol… He receives disability, and seems content to stay home all day with his dogs, watching Netflix. He takes his medication, and attends his doctor’s appointments that I take him to. I am not sure if he realizes how healthy he used to be, and how much he has lost… He did not graduate from high school and has never held a job. I feel like this is the 50 percent of my life that is not happy…. and I am allowing myself to feel the deep sadness of his situation. I have two younger children who have moved on and gone to college… their succes magnifies the sadness for me. How can I choose to think a different thought that will make me feel less sadness? I look back at pictures and feel like I cannot breathe, and wonder if there is anything I could have done differently to have prevented this. I am divorced, and my son does not have a relationship with his father, except maybe a text here or there. Thank you for answering my question 🙂