[sizzla]

Cool, understood. Just keep in mind that most psychologists will tell you that you are (or you can be) by and large in full control of your personality traits and that these things can change dramatically through your life, either through your conscious decision or through environmental influences.

So to make a determination over why you are the way you are based on how you perceive yourself in terms of a personality trait category that (Jung or not) is related to the Psychology of Types is doing a bit of that self-fulfilling prophecy.

There's nothing wrong with preferring to keep to yourself and socialize less frequently, but perhaps it would be wise to rule out other hypotheses (like, really really convince yourself that there's not something else bothering you in life). That's as far as I can speculate, because although I might claim you might not be consciously aware of the whole story, I am even less aware, it's just a pattern that I noticed with some friends and some of them, years later, refer to those periods as periods of depression, some of them even talked to a good psychologist about it.