The Secret Life of Walter Mitty
The author's text structure defines Walter Mitty's personality as timid, inscrutable, and depressing.
First, Walter Mitty can be characterized as timid.
Mitty is shy and does not stand up for himself as his wife is someone "who has yelled at him" many times. He allows his wife to put him down all the time without defending himself.
Secondly, Walter is a mysterious and awkward man.
Walter Mitty does not travel out in public much due to his awkwardness; additionally, he does not participate in many public activities.
Third, Mitty is depressed throughout the majority of the story, until he finally changes.
A passing woman "laughed" at him and he allowed her to keep laughing at him. This is an example of many put downs that Walter receives each day by the public and his wife. All of these rude things said about him accumulate and make him feel unwanted and depressed.