My mom doesn't like one of my female friends

My mom has a very hard time trusting women. In her college year she had a best friend who drugged her and molested her and let her brothers take turns with her... Ever since my mom doesn't really have female friends. My mom told me when I was younger that women have a natural caution alarm when it comes to men. They get that feeling when a man is dangerous. But most women don't have the same alarm with other women and a woman can use that to their advantage. They can pretend to be your friend and manipulate the hell out of you because they know women trust other women more. She told me I need to develop the same caution alarm that we naturally have with men with women because females can be extremely manipulative.

My mom was never mean to any of my female friends, it just took her a while to trust them and I do have some she doesn't really like but respects. But this particular friend I have. This girl friends me on Facebook and started messaging me. She seemed nice and we've been hanging out. My mom met her a few times and tonight my mom told me she doesn't trust her. She doesn't know what it is but something is off about her and she has a very bad feeling. This caught me off guard because even if my mom didn't exactly trust my other friends, she never said anything like this before. My mom looked legit scared for me. She said she can't tell me what to do but to please watch myself with that girl because her gut is telling her she's a safe friend to have. I'm not really sure what I'm supposed to do with that information. I can't just leave her because my mom feels weird about her. She's a very lonely person. She told me all her friends just dropped her and blocked her when she was going through a really hard time and I promised her I wasn't like that. I just really don't know what my mom expects me to do.