Question about social-emotional reciprocity.

I understand most social cues, but I have severe problems with social-emotional reciprocity.

Why is only understanding social cues not enough?

I tend to show abnormal facial expressions to a mild degree and some abnormal body language as well. It takes a few minutes for people to find out that I have Autism Spectrum Disorder or odd.

people are weird and it's stupid.
People used to think i was quite rude as a kid because i look away from people while talking to them because faces are a lot of information. I still don't know what colour eyes my girlfriend has and that's ok. I still don't get tone too so i cna't tell when people are making fun of me or making jokes and stuff. I have picked up on hyperbole though so sarcasm is less hard.