Actually in this new game I am at level 16 and I sneak everywhere to try and get SNEAK leveled up. There are times when I just say, "The heck with it." And, open up the console and type "player.SetAv Sneak 100." And, be done with it.
Which is why I don't play on a PC, lol. Because I'd be doing the same thing

I did notice that, on the PC version I also own, when I force my skills up like that it doesn't affect my character level. I went "console command happy" one day and put all my skills at 100 thinking that would level me up. At the end I was still level 1

No! It's just a darn slow process that annoys the heck out of me. ...
Sounds like good old fashioned burn-out to me.
Perhaps stepping away for a bit would do you some good. Focus on another game, or just something else entirely, then come back to Skyrim with a fresh point of view. Instead of "doing what you usually do" when you set out, pick a different area to explore, or set some kind of goal like "I'm going to discover and clear every single dungeon, shrine, or location that exists in this Hold." ...and then go for it. Levels be damned.
A watched pot never boils my friend.
