What a horrible time for you. I am so sorry.
Not a substitute for practical help following assessment - but sometimes voluntary agencies such as AGE UK will provide a bit of extra assistance - like a volunteer - perhaps a fellow gardening enthusiast? - to sit with the more ill/disabled person at regular intervals to provide company and to allow the other person an hour or two to get out of the house/go shopping/ get their hair cut etc.
Also, if your DH continues to need 24 hour care for a while you may be entitled at some point to respite.Find out what you can get, get a GP referral, and take what is on offer when you feel able to at regular intervals. Family members can keep in touch/visit when you are away to make sure all is OK.
It is not uncommon - for formerly active and capable older men especially needing care - to be unaware of the burden this places on their other half over a period of time, and to be unwilling to have outside help. They do not mean to be selfish, probably, but the outcome is the same.All this attitude does is to wear out the partner, to the extent that they risk having a breakdown. If this last happens, then the husband has no choice in many cases other than to be looked after by strangers - and probably then not in their own home - for a (possibly indefinite) period of time. This is the last thing they want, and it is much more costly to a health authority than providing short breaks for respite and enabling the carer to keep up morale and cope better.You especially should make sure you do not lose sight of your own needs.
In the authority I worked for prior to retirement, respite could be claimed for up to 16 weeks a year depending on the extent of the need for support.And couples could apply to have breaks together in hotels geared up to deal with disabilities of all kinds.You may not be ready to think about this at the moment, but it helps to have something to look forward to. And don't lose touch with your friends.
Do make an appointment talk to your GP about YOUR feelings and your fears. S/he may have some useful suggestions to make. Good luck.