Oh my dear. How hard it is to watch someone we love suffer. And yes, take care of yourself. Do it for yourself, and for him. Who else will care for him as you do?
You are his advocate. It's not a role you planned on, but try to think of it this way: In a long-term marriage, one of you was going to become ill first. There was no way to know who would be the patient and who would be the one taking care. Life is very whimsical, in a terrible way.
I feel for you deeply, as I know you understand. Sleep is very important. Do they have gummies there (legal) that are a mix of THC and CBD? These, often taken before bedtime, in modest quantities, can help to induce sleep and aid in a longer sleep.
I hope this trying time for both of you passes soon♥️