I had something kind of similar happen with my college friends, although only like 13 years ago. I've thought a lot about it because while I was admittedly not a great friend at the time, I was also going through a really hard time and they were very much not there for me. So I dunno, I feel like i had to accept my role and forgive myself to come to peace with it. Which isn't the same as whitewashing history, but is kind of like...
I look back in hindsight and see a collection of imperfect people. I went through something difficult during the exact time we needed to seal those college bonds in blood to keep them going. I was not a good friend during that time, and they were not good friends during that time.
I am not articulating this well at all but I got closure by forgiving myself and forgiving them. Nothing we do and say is in a vacuum. All relationships come from two people (or more) all having a role in the outcome. And its important to grant yourself permission to see that it probably was not all your fault, but it was somewhat your fault, and that despite all that fault, none of you have to be bad people. You don't need to accept a label of 'bad friend' or 'bad person' as part of your personal definition of self in order to believe that you made mistakes back then. And you don't have to think those friends were perfect just because you make a mistake back then.
I think thinking about friends as for 'seasons' helped me too. Those friends were amazing and I love them, despite all that happened. They were perfect for where I was in my life then. Open yourself up to new friends OP, and don't put the pressure of an expectation of a lifelong bond. You can be thick as thieves during one season, distant or not talking the next, and it doesn't devalue what the friendship once was.
This is kind of rambling sorry if it doesn't make sense, but good luck

And what you're feeling is normal IMO