All of my regrets

I burned two friendships to the ground by drinking. I made promises I didn't keep and they became fed up with me and left. Both of them were my rock, my best friends and I miss them. I miss them so much that my heart has been aching for days. I feel so guilty and sad. I know I made a choice. I've been told by others to move on but how does one move on from feeling so much heartache? It's been really tough going through this alone.