People who say it's fine when it isn't fine aren't always lying - they may be running an old calculation that says the cost of the truth is higher than the cost of carrying it alone - Silicon Canals

"There is a kind of emotional accounting that often begins early, before a person has the language to describe it. A child learns what happens when they say a feeling out loud. Sometimes the answer is comfort. Sometimes the answer is escalation, dismissal, embarrassment, or an adult who suddenly needs to be reassured that they are not the problem."

“It’s fine” may be said without lying, because the speaker may be relying on an old calculation about what it costs to tell the truth. The cost of honesty once outweighed the cost of swallowing it, but the math may no longer be checked. Many interpret the behavior as avoidance or mild dishonesty, yet the speaker may be telling the truth about what they can consciously reach in the moment: ending the conversation before it costs them something. Emotional accounting can begin in childhood, where expressing feelings leads to comfort or escalation, dismissal, embarrassment, or reassurance demands. Over time, suppression can feel like personality, and patterns that run without supervision stop updating.

Read at Silicon Canals