Just realised I somehow accidentally deleted my last post when trying to edit it.

You really can't speak on behalf of all introverts. I've been plenty lonely throughout my life, as I'm sure many introverted people have been.

At the end of the day, there's no point comparing yourself and your problems to others. There will always be people better off than you, and people whose lives you envy. It's not productive and it's just gonna make you feel all the more depressed about your own situation.

Yeah, making friends later in life can be hard. I have zero friends aside from my significant other. No idea how I'd even go about making new friends either, so take what I say with a pinch of salt, but you could try meet up sites to try and find people with similar interests and what not. Just be aware of your own safety when meeting people you barely know off the internet and what not.

Even when you have friends though, you have to remember it's impossible for them to always have time for you, and you to always have time for them. It is important to be able to entertain yourself now and again during your spare time when you can't hang out with your friends. I think it would be a good idea for you to look into some hobbies you can do by yourself, but also with others when the opportunities arise. You can play some video games with others, for example.