Sorry to hear about your husband's accident, and bless your Dad for working at the grass.
Like L&M, I'd see if someone wanted to graze it.
Failing that, a few store wether lambs, of the local breed, shouldn't be too hard to look after (certainly no more than pygmy goats!), and you'd send them to the butchers/auction in the autumn when the grass had slowed down anyway.
I think the question is not so much which is more work, sheep or grass-mowing, but which you'd prefer to do. I prefer the former
The other thing is, is there someone who could cut it for you with more major grass-cutting equipment. For example I have a quadbike and towed mower, which would make short work of a relatively flat 2 acre field.....