Your question concerning Chopin's The Awakening is an ethical or moral or religious or personal question, rather than a literary question.
The work of art is what it is. It is an author's attempt at a revelation of human existence. And suicide, almost by definition, is committed by people who feel that they are in a hopeless position. They feel hopeless. They feel that there is no other viable option available to them.
There really isn't any agreeing or disagreeing, then. At least not in the literary sense. The work is what it is. Edna's reasons are her reasons, not anyone else's. Agreeing or disagreeing is judging Edna, rather than experiencing her fictional life and allowing oneself to be exposed to ideas and experiences not one's own. Characters in sophisticated literature should be understood and experienced, not judged on moral grounds with one's own particular set of values. Edna is not a case study--she is a character in a fictional work of art.
And that is an issue worth considering. Does Edna have to die to complete the work of art? Is her suicide necessary to complete the work of art? Would the work be compromised if she doesn't commit suicide? I suggest the answers to those questions are the answers you should be looking for.
And I suggest that the ending is a beautiful ending. It is the natural result of the narrative. It is what had to be. You can argue that the work as a whole is a bit didactic (designed to teach or make a point). But as it stands, the ending is the natural conclusion to what comes before it.