Desperately needing help/ suggestions to move on from ex

Hey guys I hope everyone is doing well and staying safe. So I’ve never really done this before so bare with me hahaha.

So basically I’m having trouble getting over my ex. We broke up over 2 years ago and I now have a new beautiful loving girlfriend who I cherish yet I still constantly think about my ex. Our breakup wasn’t conventional, I was told if I got help for my drinking we would get back together but basically after 3 months of me messaging to check in she said I don’t think we will get back together but maybe in the future. 2 months later I was told after trying to savour any last chance I had getting her back she said I think it’s best we stop talking. As I never really got closure or told directly “ I’m breaking up with you , we are done” I still have lingering feelings and often think about my ex and compare her to my current partner. I can’t help this and I wish more than anything I could move on. I love my current partner and know she is the best thing that has ever happened to me. I feel it and know it in my head but why don’t I feel it in my heart. I want to be with my current partner for the rest of my life but I feel I can’t give her the man she deserves when I still think about my ex constantly!!

these lingering thoughts cause me Great Depression, guilt and sadness and I would appreciate any techniques/ tips or methods to move on from your ex completely.

I understand this is a difficult situation but I don’t know what else to do.

THANK YOU EVERYONE