Emergency departments can ban violent patients from seeking care for non-urgent problems. However, they cannot deny care if they have a life threatening condition.
I get the impression the psychiatrist wants to ban you from in-patient admissions only. The decision is probably based on your diagnosis. One of the treatment protocols for your diagnosis is to avoid hospitalization, since it can make patients worse.
Do inpatient stays help you or do they perpetuate suffering?
Being in perpetual crisis is not a healthy way to live. It's a symptom that something in your life is not working.
Are you still planning to get off all the substances? I think that will help you tremendously, especially if you have appropriate supports in place.