In the end of Kate Chopin's novel The Awakening we find the main character, Edna Pontellier, swimming toward the deepest side of the ocean, nude, and allowing herself to drown. This is symbolic of a baptism, or a ceremony of submission in which Edna gives herself back to the ocean, to nature, and to life. Her suicide is not vicious nor was she in a state of desperation. It is actually a very passive transition that, Edna feels, needs to occur.
When you think about it, Edna had just realized how her life is certainly not the life that she would want to continue living. She has discovered a form of love that she will never experience again. She has reached her zenith: What else does someone with the amount of passion, and the need for love, that Edna has can do?
If Edna is alive at the end of the story then she would have to go back to a life that she does not recognize anymore: A wife? a mother? A submissive person? She is none of those things in her heart or mind anymore. She finally finds herself, and realizes that she lives in a world that would never be at her pace. She will never be the same again. Hence, why not ceremoniously go back to the womb of the ocean, the world's source of life?
Conclusively, I would not change the ending at all. I think Edna's martyrdom is a lesson in life and love altogether.