Hello @marilyn1942, and Welcome to Connect,

Thank you for sharing your story; you must be feeling so frustrated, and sad with this interaction.
@lesbatts has given some great advice and suggestions; I also wonder if your son feels vulnerable, or 'powerless' about his situation, and is reacting by lashing out in anger so as to feel in control of things?
Sometimes, verbally recognizing the cause of low self esteem, or acknowledging how hard this may be for him too, can make a difference.
What you shouldn't do is assume blame for his problems or shortcomings; you have to take care of yourself first, so that you can take care of your family.

@marilyn1942, have you thought of getting your son to see a counselor? A neutral mediator, sometimes, may be able to reduce tensions and anxieties and, hopefully provide a solution that neither party may have thought of.