Reincarnated as a Vase Princess: What Should I Do?

Cultivation Novels with a Selfless Female Lead

I really want a story where the heroine blows herself up to save the world, or to protect the people of her sect, while fighting off the demon clan. After she's reborn, she realizes it wasn't worth it. The people of the world weren't worth saving. She did all that for nothing. Then she stands on her own, ideally as the sect's senior disciple.