The Painted Door by Sinclair Ross reveals how a lack of communication, even in the most devoted individuals, can lead to difficulties, misunderstandings and isolation. It is sadly ironic that the door, the main symbol, reveals that John indeed witnessed Ann's infidelity.
Denial is a theme that is prevalent throughout and Ann, by her own admittance, realises that a coat of paint will make little difference to the door - and by inference - her life. In fact, it makes a big difference and is what reveals to her that John really did come all that way through a terrible storm just to be with her.
It is relevant that it is a door, usually a symbol of a new beginning when another door opens or it can infer open communication - as in "open door policy"- or it can mean the end of something and closure. Ann has no idea when she allows Steven to spend the night, that she is already closing the door to her future. The fact that she realizes too late that John is all the man she could have ever wanted and Steven just used her intensifies the use of the painted door as a symbol.
The harsh storm foreshadows events and is symbolic as storms often destroy and John loses his life in one such storm. Anne's life with John is represented by the storm and her imagined life with Steven- which may be passionate - lacks depth; just like a fire that burns but cannot sustain itself. Heat and cold are symbols of Ann's conflicting emotions and her isolation is obvious, intensified by the snow. "It was the silence again, aggressive, hovering. The fire spit and crackled at it" and Anne is comforted by it. Later, having realised her mistake, she no longer sees comfort in the fire and "now suddenly they were the swift little snakes that this afternoon she had watched twist and shiver across the snow." Anne now wants to feel the cold in her "need to suffer and atone" as her guilt is unbearable.
The playing cards represent the fickle nature of men and women and, although there is an element of chance in a game of cards, it is often how you handle the cards that assures the outcome. Anne has been "dealt her hand" but chooses to imagine a different life with Steven and when opportunity presents itself, she symbolically "deals another hand." It is not a risk worth taking!