Hi Nanny 7,
I'm sorry that you find yourself in such a difficult predicament. I certainly don't think that you are being "cruel" for trying to find a solution to a difficult situation.
You have asked for advice, but I can't really offer you any advice, as such. As you suggest, it may be a good idea to speak to his G.P., but, in my opinion, his doctor won't be able to "make" your husband understand his diagnoses, or coerce him into accepting treatment for either his dementia, prostate cancer, or even his incontinence. Nor can anyone coerce him into accepting home carers. It may be that the time is approaching that you come to acknowledge that you cannot continue to look after him at home for much longer without assistance from home carers (which he refuses). If or when that time comes, you could ask for him to be assessed by the Local Authority under the Mental Capacity Act as to whether he is able to make an informed judgement as to what his needs are and, realistically, how they can be met (taking into account your own health issues and his refusal of home carers). If he is deemed to lack capacity to make such informed judgements, then decisions can be made for him. This might include admission to hospital for assessment and/or transfer to a residential or nursing home. This might not be something that you would want right now, but you have indicated that you have your own health issues, which are likely to worsen over time. So, you may want to start planning for such an eventuality.
Best wishes,
JedSee.