My literally does not give a flying hoot about what he looks like. Never has. It's not even on his radar to think about his appearance.
This is fine most of the time as he works outdoors. He's hard working and lovely in other respects.
The problem happens when we want to go somewhere together, which is fairly rare.
AIBU to expect him to get a haircut once in a while, or trim his beard? He looks like a tramp. I just can't help being embarrassed being seen with him, is that really bad?
I buy all his clothes (and pay for them) because if I didn't he'd be ten times worse! I still can't persuade him out of his shitty wellies for the school run. His car is similarly embarrassing.
I don't want to be a nag but it's always really bothered me.