Is a girl's recounting of situations that anger her with her friends and neighbors considered backbiting, especially given her feeling of guilt about it?

The question posed by the enquirer is unknown. If the question is about women's work, its answer has been previously given in Fatwas no. 32421, 3859, and 34012.

Backbiting is to mention your brother with what he dislikes, and it is forbidden except in six situations, one of which is seeking redress to remove injustice. If what the sister is experiencing falls into this category, then it is permissible to the extent of need.