In my case at least, I absolutely believe the ability to "get over" bad social experiences can turn someone into an introvert or extrovert over their lifetimes.

In my case at least, I absolutely believe the ability to "get over" bad social experiences can turn someone into an introvert or extrovert over their lifetimes. For example, no amount of conscious effort allows me to let go of bad social encounters, so instead I have a treasure chest of repressed memories over several years (my brain likes to pull one out at random late at night just to torture me sometimes). Further social interaction always puts me at risk of accumulating more bad experiences that can't be let go, so as a result I have to work extra hard whenever I talk to strangers or acquaintances to overcome the anxiety and "perform well". Around close family where I can be myself, social interaction is not exhausting and I feel like an extrovert. In other words, perhaps inability to "get over it" leads to social anxiety which leads to taxing social interactions which leads to introversion (...which leads to suffering). Doesn't necessarily explain introversion for all people, though.