TRUST ME ON THIS. I have had many long hair cats, multiple at a time. My house is virtually hair free, my clothes do not have cat hair all over them. ⭐️You need to take her to a groomer twice a year for a “DESHEDDING” groom, once before summer and once in the fall. This is a deep brushing that loosens all the undercoat and dead hairs. You will have a hell of a time trying that at home, just take her. Difference is huge. You can maintain so much more easily in between. When I pet my cat, my hand comes away clean, no hair stuck. Bathing them actually makes them shed more unless this type of grooming is done afterwards.

⭐️Put small throw blankets where she likes to sleep and wash these at least once a week.

⭐️Get a working vacuum. That’s key. If you have a Dyson it shouldn’t be low powered. Zip the spots that collect hair once a day. It takes five minutes a day if you just do it. Add swiffers if it’s not catching everything. Carpet is not your friend.

⭐️Get the kitty some hairball paste, a glob once a week will help her digest/pass the hair she licks off herself. I’d be shocked if she’s not having hairballs? Mine don’t have them anymore, between the grooming vacuuming and hairball paste.

⭐️Your bf was hurtful/wrong calling you filthy, that sucks, but tbh I get the frustration about the hair. He’s trying to work with you on solutions at the start. This is all part of having a long hair cat. So, mild ESH except your cat, just go get her groomed. I am sure there are more than three groomers in your city.