Christina, your dad needs 24 hour care that only a nursing home can give. That is what they are for. Taking care of someone with dimentia or altheimers is anot like taking care of a sick person. It will wear everyone down and nursing homes have the staff to handle him. If he had any other disease that required medical treatment, it would be obvious that under a professional's care is what is best for him.
It is too bad that siblings have to saddle you with this unneccessary guilt.
My mother in law had to be placed in a nursing home for the last 2 years of her life. She had altheimers. During that time, my wife had breast cancer and had to have surgery and recovery. We both work and there is no way we could have cared for her and dealt with our personal problems.

Do not feel bad or like a failure if you have to place your dad in a home. You ar not health care professionals, and he will get very good care there. All you have to do is visit him often.

What you are dealing with is heartbreaking, but it will hit all of us. You need to take care of yourself too. Get help and don't for a moment feel bad about it.

Ed