I would spend a game or two (or three if necessary) working on my spares, looking at what I'm targetting and see if the misses are due to being too fast with the feet, ball speed, missing my target, dropping the shoulder, or any other possible combination. I agree that when you miss a lot of the same spare, espcially one that you can get 9 out of 10 times, it's usually a mental block of some sort.
There have been some weeks in my Tuesday house where I've missed the same easy spare 3 times out of 4 in a given night. That following week I took out the plastic ball, spent two games shooting the 7 pin, then 10 pin, 4-7, then 6-10, 2-4-7, then 3-6-10 and went back and forth...
I'm sure you'll be back to your normal 10 pin making capacity in no time mumzie, let us know what you do to get out of the slump as all would be interested in what methods worked best.
Matt