If you are already on hospice and have made funeral arrangements, let them know when the patient enters hospice. Set up rules of visitation. who can visit and when, how long they can stay. In fact, there are those who will hover like vultures, no matter what you want. They do not mean to, they are just helpless, like the rest of us. A good hospice can provide it not for just the patient, but the family and friends.
Bereavement counselors can help the mate and family the patient after a death.
Anything beats tearing yourself apart with grief. If you are depressed, get something from the family doctor. It does not take a shrink. Pick a place where you can go to get away from the patient, for your good and theirs. Even an hour will help.