She won't die right?RIGHT? ╥﹏╥

No, I think it's just the her of the first timeline that is dying, not the her of this one. In the first timeline, she waited several thousands of years in the time space just to come to him with the way to kill one of her kind. The her of this timeline had realized just how much she adored him and treasured him to risk so much to be able to help in the next timeline. So it's just a way of putting to rest his past attachments with the her from the first timeline, even though the current now knows everything the her of the previous timeline did for him and why she did it.