My simple bit of help would be to do some unconscious putting on course.
Once you have done your read, and can see a line going back and forth to the hole that the ball will travel along, and have made your practice strokes behind the ball looking at the ball and hole. When happy with pace and length of practice stroke, get to the ball as quickly as you are comfortable with.
Aim the putter looking at the hole, then get comfortable into your stance, ALL THE TIME LOOKING AT THE HOLE, then look back to the ball and as soon as you see the ball, make your stroke, no thoughts, not anything, MAKE THE STROKE.
The only variation I would add to this once you are putting well again is to follow the line from ball to hole, then follow it back again in reverse. As you follow it in reverse as soon as you get to the ball make the stroke. NO MECHANICAL THOUGHTS!
Mr Nicklaus tracked the ball to the hole and back again, that's pretty good advice in my book.
Do all your stroke work on the practice green/house/office. Once on course you have to just react. This sounds like simple advice but it works, there are many other NLP/Mind techniques but I was taught this one for chipping issues, and combined with mechanical work off course this has solved my problems.
I hope this helps as if you do what you do on the practice green, your stroke is good. We can all improve out reading,pace,aim and stroke on the practice green, but we need to work on our mental routine too.