Advice on getting over a break up

Hey everyone, I was in a 6 year relationship, from when I was 14 to 20. It ended in May of 2021 and I still think about them everyday. I feel so pathetic for that because I think they've moved on and don't even think of me anymore. I think one of the biggest reasons I'm not over it is because I don't 100% know why I happened. They said they felt distant towards me. But not why exactly. We also had 2 cats together which which considered my best friends. They still have the cats thankfully. But yeah, it's been half a year since it happened. But I still love her :( and I wish we could be together again.