To believe or not to believe???The question which the MAIN CHARACTER ask himself

The protagonist (from Ancient Greek πρωταγωνιστής (protagonistes), meaning "player of the first part, chief actor") or main character is a narrative's central or primary personal figure, who comes into conflict with an opposing major character or force (called the antagonist. 

   If talking about the main character of the story, I'd like to say that the author is the protagonist. The narrator in “The Yellow Wallpaper” is a young wife and mother who has recently began to suffer symptoms of depression and anxiety.However, the reader never learns her name. To my mind it's very symbolic, because Gilman has cleverly taken the reader into the inner-most realms of a woman’s mind and experiences, yet the woman in “The Yellow Wallpaper” remains anonymous, a reflection of her status in society.

To describe the character of the story the author used inderect characterization. In the such example we get to know that the woman is really very nervous: "John is a physician, and perhaps - (I would not say it to a living soul, of course, but this is dead paper and a great relief to my mind - ) perhaps that is one reason I do not get well faster. You see he does not believe I am sick!  And what can one do? If a physician of high standing, and one's own husband, assures friends and relatives that there is really nothing the matter with one but temporary nervous depression - a slight hysterical tendency - what is one to do?” From this words we can imagine how difficult this woman is, and I don't know if it's her temporary emotional state or it by her illness. 

The main charecter tries to be the perfect wife, but she always disagree that she has a problem, I think she doesn't trust her husbend “So I take phosphates and phosphites—whichever it is, and tonics, and journeys, and air, and exercise, and am absolutely forbidden to ‘work’ until I am well again. Personally, I disagree with their ideas. Personally, I believe that congenial work, with excitement and change, would do me good". 

Moreover, as the one thinks which helps her to feel better was writing she feels really angry with husbend, because he can't understans her: “It is so discouraging not to have any advice and companionship about my work.” From this misunderstanding with husband and all people in general, the narrator  begins to find comfort in the hideous yellow wallpaper that covers the walls of the nursery:“I have found out another funny thing, but I shan’t tell it this time! It does not do to trust people too much.” She gradually begins to see a female figure trapped behind the bar-like pattern of the wallpaper and realizes that both she and the figure are suffering from oppression and imprisonment. In oder to show growing insanity with each passing day, the author used choppy prose and disjointed stream-of-consciousness. Eventually the narrator becomes a "creeping woman." The first indication is when she says, rather startlingly, "I always lock the door when I creep by daylight." Later, the narrator and the creeping woman work together to pull off the wallpaper. The narrator writes (or perhaps says -- there's some debate about this), "T  here are so many of those creeping women, and they creep so fast." So the narrator is one of many, she losses her face, she losses herself......

    The other main character is  more indroduced to us. His name is Jone. As for me, I think he  does not take her illness seriously. John treats her like a child, calling her diminutive names like "blessed little goose" and "little girl." He makes all decisions for her and isolates her from the things she cares about. His actions are couched in concern for her, a position that she initially seems to believe herself. "He is very careful and loving," she writes in her journal, "and hardly lets me stir without special direction."  her words also sound as if she is merely parroting what she's been told, and "hardly lets me stir" seems to harbor a veiled complaint. To my mind Jone doesn't love her, because he speaks to her as if she is a whimsical child, imagining her own illness. "Bless her little heart!" he says. "She shall be as sick as she pleases!" He does not want to acknowledge that her problems are real, and so he silences her." Her wife understands it and maybe even eccepts his position : "John does not know how much I really suffer. He knows there is no reason to suffer, and that satisfies him."John can't imagine anything outside his own judgment". So when he determines that the narrator's life is satisfactory, he imagines that the fault lies with her perception of her life. It never occurs to him that her situation might really need improvement.