In "State of Divinity", Lin Pingzhi wanted to get his revenge on Yu Canghai for his family's tragic death. He did so by joining Huashan Sect, and shortly after, by learning the Bixie Swordplay to exact his revenge on those who wronged him.
If I'm not wrong, Lin Pingzhi married Yue Lingshan with an ulterior motive. He wanted to prevent Yue Buqun from killing him after he obtained the Bixie Manuscript. However, why did he not escape from Huashan immediately and team up with someone he knew pretty well, his ex-senior, Linghu Chong?
Yes, I am well aware that at that point in time, Linghu Chong was infamous for being seen together with the Demonic Cult, and even suspected of stealing the Bixie Manuscript for himself, but Lin Pingzhi seemed aware that Linghu Chong was innocent of the crime in "State of Divinity 1996". In fact, he said so himself, to Yue Lingshan, that Linghu Chong had so many other opportunities to steal the Manuscript if he really wanted to. The fact that he didn't do so, and instead "chose" an unwise time to do so, proved his innocence in Lin Pingzhi's eyes.
I might have misunderstood something, however. It's been ages since I last read the novel, and I'm currently rewatching "State of Divinity 1996", and this kept bothering me.