Complex sentence: Not knowing what else to do she had stayed around the school looking for a way back into Grey World to save her friends but now after being in the real world for awhile decided that both she and her friends were better off in Grey world.
Split into simpler sentences: Not knowing what else to do, she had stayed around the school looking for a way back into Grey World to save her friends. Now, after being in the real world for awhile, decide that both she and her friends were better off in Grey world.