Introversion/extroversion doesn’t have anything to do with chattiness or social skills, as I understand. There are plenty of shy extroverts around, and loud introverts.
The key question is: what do you do when you feel down, and need to “recharge your battery “? Do you look for people to spend time with- or do you need time alone?
I’m an extrovert. When I feel drained, a couple of hours with a few friends sorts me out. Even being in work with my colleague helps. Or annoying my kids :-) Being left alone in that situation just makes me feel worse: I need that period of interaction to tide me over.
My friend, she’s an introvert. When she’s had a hard week, she seeks solitude. She needs time alone to get ready for her next set of interactions, as they drain her.
My friend is no more shy or socially restricted than me. But if she’s feeling down, the last thing she wants to do is go somewhere busy. Whereas I would seek out company in that situation.
My SIL suffers social anxiety and depression. she’s not choosing to be like this. It makes her life pretty hard and I don’t judge her for it. She’s already convinced that people think she’s boring and hard work, why make her feel any worse?