Introverts are always there when you need them, but they also need space. You see.. they listen, they care, they empathize. When they give, they give like a candle burning from both sides. But there's a limit. They're human. They're there, just let them catch a breath.
Only a fool would think introverts are unfriendly. Yes, they don't have a large group of friends, but that doesn't mean they're unfriendly. They're warm & welcoming people. Kind, caring, and highly empathetic. Great listeners. But, they're close with only a few. That's all.