Why did Elysia sacrifice herself?

I'm curious to understand the motivations behind Elysia's self-sacrifice. Was it a noble act driven by a deep sense of duty or sacrifice for the greater good? Was there a personal reason that compelled her to make such a difficult decision? Was it a last resort measure to prevent an even greater catastrophe? Or perhaps, was it a combination of these factors that led her to take such a drastic step? It would be fascinating to delve deeper into her thought process and the circumstances surrounding her decision.