Can a spouse be a caregiver?

Of course a spouse can be a caregiver. I suspect that your question is really about being paid – please explain.

I'm confused on your question, as of course there are many spouses that are or have been caregivers for their spouses, myself included. I was my husband's caregiver for many many years until his death 6 months ago. Are you perhaps asking if a spouse can get paid as a caregiver? If that is the question, the answer is no.

Maybe this will be helpful:
https://www.agingcare.com/articles/how-to-get-paid-for-being-a-caregiver-135476.htm

If you mean getting paid for it, probably no. And I know that doesn't seem fair because sometimes the Caregiver has had to leave a job to care for a spouse so it leaves them short on money.