does anyone have a friend breakup that has haunted them for years?

I was super close friends with someone in college, who also moved to the city I live in still after graduation (she was from another city in the same state) and we stayed in touch for another 5 or so years. not quite as close but still good friends, in a way that was emotionally significant to me at least. we hung out pretty regularly and confided a lot in each other.

for context, I've struggled with depression and anxiety basically my whole life so of course I've gone through periods where I withdraw socially, and unfortunately at some point we didn't speak for about a year. when I tried reaching out again, she never responded. I waited a few months and tried again. then some more months and messaged on social media. I've since tried a couple more times, on different channels, spread out over years and years, and never heard anything. I only stayed in touch with one person we knew in common who also didn't hear from her, so actually the only way I know she's still alive is from linkedin. I guess it's not like we had a falling out so much as mutual ghosting. but I've always wondered if I did something. I've accepted that maybe I'll never know.

I never had many friends growing up and I still don't, though I think I've gotten better as I've been getting mental health treatment. tho I've never had a best friend who wasn't also my romantic partner. this long dead friendship has bothered me so much, and I have dreams about to this day. this close to 40, we might not even be the same people we were back then so I don't know if I'll ever try get back in contact with her again. it hurts and I get scared in my current friendships about this still.

well thanks for reading all this if you did. happy to hear any similar stories or advice.