My roommate says the AC gives her “anxiety”. We live in a swamp. How do I get her to leave it on?

I (28F) live with 2 other women (27 and 33) in an extremely humid city. All utilities are included in our rent.

The 27 year old and I keep the AC on a reasonable temperature but every time we turn it on, the 33 year old comes out of her room and turns it off. When we talk to her, she has given every reason in the book. She says it gives her anxiety and she has to study. It’s so cold it’s making her sick. It’s too loud. She just refuses to leave it on.

I know it’s not unreasonably cold because I’m way too skinny so I am always the cold one. I wear gloves in the office during winter time because that is how cold I get. I shiver when everyone else is fine.

The 27 year old says she’s going to move out if this doesn’t get resolved because it’s ridiculous (which it is). But I don’t want her to do that. How do we resolve this?