Need some mature advice because I'm losing my mind and I'm impulsive and stupid things when I'm depressed

So there's this girl I posted about here before who used to be my workplace buddy but as soon as a popular girl started bullying me this buddy of mine became closer to her and left my side. At first she stopped saying hi altogether but slowly she started to have this diplomatic superficial professional friendly mannerism with me where we would occasionally say hi to one another but I was like no no no no sir! No superficial bullsh.it with me! So I stopped saying hi to her altogether.

Anyway so when she found out I have a private instagram she started sending me follow requests that I would ignore. She would delete the request and send it again... And again... And again... At this point we were somewhat on normal terms (her terms, that is, saying hi occasionally) so well I accepted her follow request because she had sent it so many times. Anyway....but she's still like that. Doesn't speak to me when that popular girl is around. Like jeeez they act like high schoolers. I just don't want her on my instagram anymore. I just don't. I only add my friends. No workplace people. But I feel it would be a weird/high schooler thing to do. I don't know... Should I do it? Should I just remove her from my followers? She's an icky person. I don't like her anymore. Although I will always mourn our time together and be jealous of her new friendships. Because I love-hate her. It's not something I can really explain.