Try going here and see if anything Leah advises will help you:
http://www.daystyledesigns.com/freemotionquilting.htm
If your needle continually breaks I would think you have the wrong size needle as it isn't large enough to take the constant pulling motions when FMQ therefore you are putting too much pressure on the needle. Also do you have your needle put in properly?
Also you can go to Bob's at Superior Threads and view his educational tips regarding needle siza the type of thread that would help you regardless of whether you purchased his threads:
http://www.superiorthreads.com/?gcli...FYrr7QodzxA9CQ