Aimeth -- I am so sorry to hear of you husband's serious challenges and struggles.
I hope for better days to come your way.
I am wondering if you are contemplating hospice care at home or at a hospice care facilty in another location. All of those I have known in hospice care had home hospice care. Each also had a strong family and or community (friend, coworker, etc.) network willing and able to participate in the time of hospice care -- visiting, providing respite care, cooking meals, providing transportation for others in the care network, etc. For my friends in hospice care, the time seemed so short (just a week or weeks) before their passing. I have heard that this is not always the case and recall reading such a case on this forum recently.
I wonder how well it would have worked had they not had large networks or hadn't received care at home. Should the time come for me, I'd want to have home hospice care. I wonder if I have a large enough network though. There are complexities in this care with health care professionals and others' abilities and presence needed.
If you and your husband are at home now and hospice care is approved (or certified -- I'm not sure of the language) there would be elements of continuity, though, and that could be comforting.
This is just my attempt to report on my observations related to hospice care given relatives and close friends in the past. It doesn't really address how you'll know it is time. I believe all those I can recall who received the care had a large role, himself or herself, in that decision.
Hoping blessings will come your way at this so, so difficult time -- Susan