I hear you buddy. Here is what I did: for 1.5 days I did nothing else, but just lifted the front wheel and pressed the rear brake. I did this exercises for 1 hr, then took a 15 minute break and then repeated the cycle. I had to rewire my mind to feather the rear brake and use it even if I didn't raise the front high enough. In other words, I used the rear brake as the way to stop the wheelie. I intentionally didn't use the throttle or the clutch. It takes some patience, but after a while the mind "adapts" to the new reflex. As the result, feathering the rear brake and in 99% of cases, I always now use the rear brake to slow down or stop the wheelie. Really helps. Try it and let me know if it works for you.
I've been practicing it everytime i have had training sessions. It works really well! I do sit-down wheelies all the time and my friends are wondering wtf i did xD Thanks for the help dude!