The Wife is the Painter's spouse, the Daughter's mother and the primary antagonist in the game.
She appears several times before she is actually encountered.
According to newspaper clippings and other items, the Wife was in a department store when it caught fire. She survived, though horribly disfigured.
Not much is known about her life before the marriage, aside from the fact that she was exceptionally talented as a musician, despite her family looking down on her career. While critics at first saw her as an amateur, she became praised for her musical abilities. Her talents helped inspire the Artist to paint, and became a crucial source for his talent. She got pregnant before they eventually married and moved into a mansion together.
Later in their marriage, she was in a department store when it caught fire and burned her severely, causing her to become permanently disfigured. Her painful recovery, along with the loss of her beauty and ability to play, led to further tensions in their household.
She was largely wheelchair-bound, and suffered from chronic pain and random muscle spasms. Despite the Painter's attempts to seek medical help that could restore his wife, the medical technology available was not enough to undo all of the fire's damage. He began to drink heavily, which was apparently an issue he had before during their relationship, as she expresses exasperation at this in a note ('not again').
The Wife felt frustrated, as she was unable to play her instruments, and began to lash out at her husband. This caused them to have loud fights which lead to their neighbors telling them to quiet down, otherwise they would call the police. After that, the Painter began to avoid her, perhaps to avoid more loud fights. The Painter's neglect caused her to delve into herself and feel all the more isolated, and she assumed he was disgusted with her. Due to these feelings, she ended up treating the Artist in the same manner. The Artist more and more locked himself away as he tried to revive his work.
Tired of the fights, her husband's negligence, and feeling like he cared more about his paintings than her, she committed suicide in the bathroom. This is made clear with the flashback heard when you pick up the Whispered Words object, a bloody knife, where we hear the Painter attempt to get into the bathroom (believing his wife is taking way too much time), and then entering to see her dead body.
Her death is what propels him to take drastic measures to bring his career back. Using his wife's remains as artistic material, he attempts to "take back what life took from him".
The wife played the violin and piano.
The wife suggested the couple get a cat before their daughter was born, but the Painter ultimately decided to bring home a dog. Why this decision was made is unknown. However, it seems that the daughter had a liking for cats as well, due to her love of her toy, Mr. Scooter.
While the marriage fell apart after her accident, and there was a disagreement over the right pet, the marriage before this seemed relatively stable, if not very happy. In her various notes post-fire, even in her suicide note, the wife mentions the past love they shared and how she loved him, even in the moments before her death. If the Painter was truly a monster, she, as angry and difficult as the wife has been described to be, would not still love him in such a way after everything they've been through.
Her monster form may instead represent his horror at seeing her beauty marred and her talents gone, a living corpse that paled in comparison to what she used to be.
It's implied that from the Painter's perspective, it's the wife's emptiness post-fire that bothers him most of all. This is said directly in the argument said if you take the Father Route of Inheritance, and due to this, he feels nothing when he looks at her, and it scares the hell out of him. This means it's possible that the arguments between the two are simply the case of miscommunication and bitterness left to fester between the couple.
The wife and the daughter are both voiced by Kristen Lennox.
Using the wife's notes as a time frame, we can figure out that she was injured sometime in late September or early October, and judging by her final note, she committed suicide on October 2nd, the following year. This means she was suffering and fighting with the Painter for a year before she decided to take her life.