This is just my opinion, but if you don't feel comfortable with the situation call the social service department at your hospital. Ask for a Psych evaluation for your dad.
I can relate to the feeling of hopelessness, when I was faced with the inability to care for myself, I was in a severe clinical depression. I needed a Psychiatrist to help me through the tuff times.
Believe a person when they say they don't want to live. The brain is amazing, but it can also go against us, when we're ill. Ask the Psychiatrist to determine if your father is suffering from clinical depression. There are many medications that can help both physically and emotionally.
All who are assisting him may feel depressed themselves, suggest that they too find someone to talk, a therapist that works with grieving and loss would be good for the group. When we loose our health and independence we need to grieve. If money is a problem, with me that's always a problem, look in your phone book or call your health department and ask for a clinic that charges based on your income. You may try the United Way in your area. There should also be a mental health Crisis line some where near you.
As one that knows where your coming from and also your father some times we all need extra help. Even when we refuse to go for help ourselves.
I know it will be hard but try to count the blessings even when they are very small.
I'll pray for you and your family and please pray for me too.