Need help trying to give advice to a friend

I this is my first year of high school and it’s been a lot happening over these months. I went to a private school for all my life and this is the 1st time in public schooling and also the 2nd time many of my friends went to separate schools. I have one particular friend that I’m really worried about. Ever since 8th grade she’s has been slacking when it comes to school and her mental health and I and other people been trying to help her and since she’s in a different school it’s been worsening, especially when it comes to guys and making new friends. At one point she’ll be falling for guys that’s not good for her and when they don’t like her back or her parents don’t approve of them she’ll go depressed and say “I’m to ugly to be liked” or “No one will ever love me” and we try to give her advice but she’ll ignore them and do the same mistake again. I haven’t heard from her for months but recently one of my guy friends told me that shes been lacking when it comes to her grades and not even trying at some points, she even failed her permits test 4 times because she believes “I’m too stupid to drive.” I want to talk to her and try to help but it feels like I’m walking on eggshells. Any suggestions?