Advice on bad mentor

I’ve been interning at a PE firm for the last 3 weeks, the people that work there are some of the nicest and smartest people I’ve ever met. I have 2 mentors that I work through, one of them I have had great experiences with where I have gotten great feedback and an environment has been created where I can really learn and work on areas of weakness. With my other mentor, she has been treating a project we are working on that according to the other interns, they worked as a team with their mentors and have been guided through it, whereas in my experience my mentor has used this as an opportunity to dump the work on me and give no guidance. She has also created a really negative environment where I am afraid to ask questions because she makes slights and talks down to me when I do. I have had overwhelmingly positive experiences with everyone else at the firm but this has really cast a shadow over the entire experience. To top it off, because she is on my mentor team, she plays a major role win my performance evaluations. I have spoken to the other interns and I have been working much more hours, both during the week and on weekends and have been receiving a fraction of the guidance. Any advice on how to navigate this would be great.