Don't expect a game to change. after 10 years it's still the same. And like anything, you can grow tired of it.
I Love warcraft in general, and i used to be really addicted to World of Warcraft, but now my passion for the game is somewhat gone. But i still love the lore so i keep playing, doing quests and planning on raiding again on legion.
Take a break, i didn't played warcraft seriously the whole WoD. The game will never be as good as it was when you started, but it will be great again if you stop for a while and then comeback to it to find that it didn't changed that much and it still the Warcraft you liked to play back on the day but with new stuff to do.
i'm playing and enjoying it. But i hope blizzard will come out with a WoW2 with better graphics and gameplay. i don't even play PvP on WoW anymore because of Overwatch. I almost don't see the point of doing PvP on WoW when Overwatch is a much better PvP Game in almost every way. I know theres alot of networking, technology, design issues to making Overwatch gameplay into an MMO and it's not fair to compare both games. All i'm saying is that i would love a Warcraft themed game with Overwatch fast-paced gameplay without lots of info on the screen.
That being said, i would love to see PvE Content on Overwatch as well.
TL;DR: Nothing last forever. Take a break. You can enjoy WoW in the future just like you can enjoy playing Super Mario World for SNES after not playing it for some months/years. There's alot of Fun games and other stuff to do out there.
Also, extra tip: don't try playing another MMO, it will hardly be satisfying. when i took a break from WoW i tried WildStar, TESO, Guild Wars 2. They are all pretty awesome, but all they did to me was wishing WoW was upgraded to something else so i could just play wow. Right now, i'm much more addicted to Overwatch than anything, but i've been playing WoW and enjoying it again.
That's my opnion. I'm bored at work wishing i could play games so i'm posting on forums there and there. :T