According to Jung, in healthy introversion you still find social relationships and interaction rewarding; it's just that you get exhausted more easily and need more alone time to do your own thing.
In social anhedonia as a trait (not as a state like in depression), it appears to be associated with not so much anxiety or exhaustion, but rather just finding it not rewarding, resulting in a deficiency in the motivation to socialize. Unlike healthy introversion, social anhedonia is associated with a much higher rate of mental illness, particularly schizophrenia.
When I told my therapist I think I may have social anhedonia, he didn't disagree, but now I'm wondering, how do I sort out whether I have healthy introversion, social anhedonia, just plain ole social anxiety, or both. I took the schizotypal personality questionnaire, and scored an 8 out of 9 on the no close friends subscale both times when I took it, a couple months ago and last November. The no close friends subscale strongly correlates with measures of social anhedonia. Now that I've found a new friend for the first time in a while, however, I wonder what I would score now.
I wonder how I would sort out which is healthy introversion, which is social anhedonia, and which is social anxiety?