An important area of speech which is considered constructive is that which helps to relieve someone of psychological or emotional damage caused by others.

It is permissible for anyone who is suffering emotionally or psychologically to seek appropriate help even if this involves discussions of people and events that would otherwise constitute loshon hora. If possible, names should be omitted, and only pertinent information should be shared.

The Chofetz Chaim speculates that it may be considered constructive for a person troubled by an issue to unburden himself to someone even if only to relieve himself of stress. Obviously, this applies to especially difficult situations and not to the daily vicissitudes of life.

Sefer Chofetz Chaim, 8 Kislev, Page 184

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