What is the ruling on writing down self-talk, specifically what comes to mind regarding negative feelings towards parents, and does writing such things in a diary fall under the category of self-talk for which a person will not be held accountable?

Whispers of the self are forgiven as long as they do not settle in the soul, as Allah Almighty says: (Allah does not burden a soul beyond its capacity), and the Prophet, peace and blessings be upon him, said: (Indeed, Allah has forgiven my nation for whatever whispers within themselves, as long as they do not speak of it or act upon it).

However, if these thoughts settle in the soul and include something forbidden, such as backbiting, or if they are expressed in writing or speech, then one is held accountable for them. Backbiting is forbidden whether spoken, written, or gestured. Therefore, writing about what transpires between a person and their parents, if it includes backbiting them, is forbidden. But if it is merely a fleeting thought, one is not held accountable for it, provided it does not settle.