I didn’t get so far behind as the OP, but what happened was I was just spending too much time per day on WK and neglecting other important things I had to do, so I needed to drastically slow my pace down.
From the beginning I was going at close to full speed, roughly 7 days per level.
What worked for me was to only spend time I could afford to spend on WK, whatever that amount might be. I think other people’s advice to simply do a ‘bare minimum’ of 10 reviews per day is good advice. You can always do more after those first 10, but basically start out your first review session by pushing the Wrap Up button right away.
The advantage of using Wrap Up is that you will force WK to focus only on a small number of review items until you get them all correct. It won’t add any new ones until you get all 10 correct. That way,
- You will always be able to make progress, no matter if they are old review items or newer ones, hard to remember or easy. You only have to work through 10 items. Doesn’t matter if you get each one wrong 50 times in the session, it will only count as being wrong once. In the mean time, you’ve gotten to drill on that item 50 times.
- You will always be able to succeed and get that positive feedback of a completed review session. This is the psychological piece that you need, in order to maintain motivation. It’s the dopamine kick that will eventually overcome the feeling of dread at looking at your large review pile. Even if you have 1000 items in the review queue, every time you complete 10 items, you can say to yourself, “Hey! I did 10 more items! That wasn’t that hard, actually. And I completed the minimum. Any more I might like to do today will be bonus gravy! Yum!
”
Now, 10 per day might not sound like a lot, and it’s not, but most importantly: You’re reducing your overall pace, slowing down, calming down, taking things easier, giving yourself the time you need to really learn the items, without stressing yourself out and burning out; and 10 is just the minimum! Once you get your mojo back, you can easily just start doing more and more per day. And this time, you’ll limit yourself to just doing as many as you can still feel comfortable doing, without overloading yourself.
When I slowed down, my review pile did start to build up bigger and bigger. But I knew eventually I’d get through it if I just kept at it. So, instead of looking at the total number of reviews in my queue, I focused more on the number of upcoming reviews. They used to be queuing up like 200+ per day. Now, after slowing down for several weeks, they are down to around 50 or so per day. That’s much more manageable.
Now it’s taking me like 20ish days per level, currently. And that’s okay. The earlier levels were just easier, and now I’m more at a level that’s finally a bit more challenging, and I just need to take my time with it.
Another great thing about slowing down is that it allows your Enlightened items to ripen and you finally start to Burn some! Those ones are gone from your queue for good, and that’s another good way to get a dopamine kick and celebrate some solid progress.
Just plug away at them, one day at a time, one Wrap Up 10-item session at a time. Before you know it, you’ll get back into a sustainable groove, and one day your queue will suddenly be 0/0 again, and you’ll be like, “Holy cow! I did it!” 
