I applaud your effort for writing us here and asking directly for help. There are three things that you have said that I think require some attention.
The first is the medical need for action. First, since you are seeing a physician I would ask him or her to recommend an outpatient clinic that would be able to see you for psychotherapy on a free or sliding scale basis. Therapy is a good idea so that you can manage some of your emotional needs through the help of a therapist. Many local community hospitals have this service and it would be good to capitalize on your connection with your physician.
Second, I would also recommend attending an Alanon meeting. While I realize you have not mentioned that someone you know has an alcohol issue, it may be the case where you are aware of someone in your sphere who has a problem. Even if not I would recommend attending an open Alanon meeting. Often the culled wisdom they offer is strikingly similar if you are dealing with someone with chronic mental illness (as you say your dad is) or dealing with those who have an alcohol problem. The support from such a group might be very helpful.
Finally, I would encourage you to join one of our online forums to discuss your situation with others who will understand. This is a free service and can help you get the support you need.
Wishing you patience and peace,