It'll pass. I basically quit multiple times and think I hit my end about 5 months ago. A lot of thoughts went through my mind about how I would fill the void. I hated the game and couldn't bring myself to do Classic seeing I did it when it was live 15 years ago. It was a big void. I multiboxed the game since 2008 and really in all honesty had a blast most of those years. The last 6 left me wanting and in truth I think I could have spent my money and time better elsewhere.

I'm much more confident in that now having played Subnautica, Terraria, Amnesia, much more Path of Exile/Fallout 4 and a lot of other offline games. WoW was truly a toxic addiction. Fun but expensive for what it was. In many ways it was always trash. Just more so in the latter years. Other games do the hardcore experience better. WoW MBing was unique in a sense but really so is playing Path of Exile standing on your head. At a certain point it's just you chasing an arbitrary goal.

You won't miss it nearly as much as you think you do right now. You'll adapt to it, change because of it and most likely become a better person for it.

PS: If you haven't I highly recommend Subnautica (HC for the tough guys out there). One of the most cherished games of recent memory for me and something that was eclipsed by my toxic love affair with WoW for so many years. We have a huge backlog of great experiences to visit now. Get to it!