To burn bridges - to make decisions that cannot be changed in the future; to permanently and unpleasantly end your relationship with a person or organisation. Example - "If you drop out of school now, you'll be burning your bridges behind you"
The world's smallest violin -When someone is whiningand you are tired of hearing it, you can play the world's smallest violin to provide musical ambiance to dramatize their annoying whine. This is accomplished by rubbing your index finger and thumb together and saying, "This is the world's smallest violin, and it's playing just for you."
Marauding - going from one place to another killing or using violence, stealing, and destroying. Example - "Witnesses reported gangs of marauding soldiers breaking into people's houses and setting fire to them"