I feel for ya. I swear at the top of my voice every time i accidently make a cluster out of my star pieces.
Apparently, the best way to stay safe from bombs, is to keep some star peices near the top of the board.
Anyway....
The best way to stop playing, is probably to get all the achievements, and a whopping great score on the leaderboards. I have a good score (about 2.5 million, placed about 250) but still need the 100 games of Hexic achievement.
Must... Stop.... Playing......