Hello Nick, nice to see you again
I think your post contains both the question and the answer you're searching. Take the last paragraph with it's question, and add the second to last paragraph on top of it. Do you think there is something you haven't done already? It's natural to go looking for answers Nick as you lack a proper closure but heck man, see where she headed after the break-up and think of it this way: what solid, heart warming, mature answers do you think you'll get from a frequent social drug taker constantly dumbed down by booze? I'm not bad-mouthing her, but look at her actions, she didn't cool down brainstorming what went wrong in your relationship. she didn't took her time and looked for a more stable, healthy, loving, caring, serious, mature, partner and as far as it looks she just went sideways and berserk all over the place. It's hard to let go Nick, but honestly, except fading memories of good times, to what else are you holding on? It will get easier, but nobody said it's easy and the only person that can help you is you.