Introverts don't fit in. They kinda like to be in their own world. Quiet world. Cosy world. A world full of love & good vibes. A world of meaning and deep contemplation. They like to be alone not because they are anti-social, but because they don't need people to feel fulfilled.
Introverts are not quiet, they avoid conflict. No arguments. No blah blah this & that. It's just not their thing. It's low vibe. Ego games. And they know it. They value their peace above everything else. You may think you won, but trust me they're the ones running the show.
Introverts need a lot of alone time to function properly. Sometimes even a couple of weeks. To take some long walks. To stare at some walls. To think & make sense of the recent events. If you find them acting weird. Trust me, it's time for you to go home.