These are big issues and I don't see any easy answers.

It's hard for most people to understand that you can't make friends, because it comes naturally to them.

If it doesn't come naturally, then you'll need to be taught some skills. And I do mean taught. You'll have to learn it like at school, like chemistry or a foreign language. It won't make sense straight away and you'll have to study.

I recommend Before You Leap by Kermit the Frog (yes, really). This is part autobiography, part self-help book and part just for laughs. But you might find chapter 13 on friendship is genuinely useful.

By the way, the suggestion that you start with animals is actually a pretty good idea.