How do I get him to understand it's important for me to get a break?

One of ways I've dealt with my parents over this issue, is to point out that IF you lose your health, physical or otherwise, then he will not even have you MOST of the time! You have to take care of your own self, in order to stay healthy and be able to be there for him! And I don't think you have a long debate over it....you just lovingly state the WHY you are putting together this plan and give him an idea of how regularly you will need to be getting your 'break' for self renewal and caring for yourself. I think you need to look at the caregiving like a JOB too....if you are in this for the long haul. YOU need time off during the week that is planned and you need long weekends and regular vacations periodically too....so there should be a 'back up' plan in place for you regularly. And you may need to tell his physician what you would like the 'order' to say. Also, if he falls a lot in your care, what happens if your back goes out or something? You need a back up plan just to keep him safe...along with you. You need time for your own doctor and dental appointments and self care activities too and your physician needs to know you are a full time caregiver, because the stress of that 'job' can bring on all kinds of medical/emotional issues that you need to be watched for. Be pro active with a plan!!

I would take the wonderful phrase "stop asking and start telling" and put it as "stop asking and start doing." Meaning, put what you need into place. The facts are the facts -- you can't keep this up. Facts don't need permission or agreement to be true.

His doctor can order visiting nurses, and you need them. He may put up a fuss at first, like the first time you leave a child with a sitter, but he will be OK. Go to hdsa.org and find a chapter near you that can help.

Stop asking and start telling.

Rule number one; take care of your self first period.
I understand that about 30 % of caregivers die before the one being cared for.

I agree with Joannes - do not involve yourself in a long debate over this - you have to get a break for yourself, otherwise your husband will have no carer. My mum wants me to be around all the time and I found that when I got a carer in to allow me to go out for just a couple of hours to pursue my own social needs, she showed disapproval, maybe giving me the silent treatment on my return and possibly for a day or so after. I have learnt to deal with this differently now so I never tell her I'm going out to see a friend, or do something else enjoyable. Instead I 'white lie' and say I have to go to the bank, or the doctor, or the dentist, or to do some shopping for her, or whatever - and because these are domestic chores that she can identify with and can't really express disapproval about, she's OK with it. Of course you have to find a carer who will sit with your husband so you don't then worry when you are out that he's falling or coming to some harm. If you don't have that peace of mind it's pointless going out.

Blame it on "doctor's orders". When you get a write up from your doctor, have the MD write that you need to go to the gym, or classes to take care of your self. My father's doctor encourages me to get help so I can take care of myself. She will write for in home care IF my dad meets the guidelines. If not, she writes on his visit summary that he will need to help me take care of myself, which might mean someone comes to stay with him several times a week or what ever. I don't know how old you are, but in my Dad's day (he is 94) men ruled the home. He is actually pretty cooperative now, but every once in a while this attitude comes up. Even then, the doctor knows best, thank goodness.

You get him to understand by hiring someone to come in and relieve you. You have to take a stand or else he will consume your every waking hour. You might go through a few aides coming into the home, but keep doing it until he recognizes you need some space...good luck!

There have been a few references to children...here's another! When my kids were little and I wanted them to do something like clean their room I'd give them a choice...."Do you want to clean your room OR would you like to clean the garage?" Even if they choose the garage it was still a help for me. You might try giving him the choice of a volunteer( or stay alone) OR a hired nurse?

To borrow from a commercial slogan..."Just Do It!"