How do you know when your friend and you are close? ?

Question

So my best friend is actually someone I met through politics online. We have been friends for a year and a half. We met through CANZUK, which is the abbreviation for the potential EU like Union between, Canada, Australia, New Zealand and the UK. He is from Australia and I am actually from America but am moving to the UK next year. Over the past year we have got to know each other really well, and we have shared a lot of deeply personal secrets about each other, he talks about wanting to share a flat with me when he moves to London, I am dating his best friend who he set me up with, I know all his friends in his personal life and I am the only e-friend to know them.

I guess that means we are close, one of his friends told me we are super freaking close. I asked how close is that, and she got pissed. She was the one who said out of the blue that we were really close, though.

I have Autism, and I don't know how to read people, how do I know how close my best friend and I are? How do I develop strategies for knowing in the future?

I guess that means we are close, one of his friends told me we are super freaking close.   I asked how close is that, and she got pissed.   She was the one who said out of the blue that we were really close, though.

I have Autism, and I don't know how to read people, how do I know how close my best friend and I are?   How do I develop strategies for knowing in the future?