A contributing factor for the difficulties with reading social cues, body language, facial micro expressions, vocal modulation,...and putting it all together,...is due to the fact that many folks with ASD will spend significantly less time observing and scanning the person in front of them. Over time,...from early childhood to adult,...the delays can become more obvious,...we can become "socially delayed". Our non-autistic peers have continued to get better,...and we are simply on a much slower pace. On the other hand, it's been my personal observation that these things can be learned,...and although we may have our "default autistic setting",...intellectually, if we are engaged with the person in front of us, we DO observe the nuanced, non-verbal communication. We might not be able to process and understand it right away,...in the moment,...but we do observe it. To this day, I will have interactions with people,...face-to-face,...on-line,...and it may take hours, sometimes days before my mind can have some degree of clarity as to what happened and how to respond appropriately. Unfortunately, I've already interacted with this other person and totally missed their point, their feelings, and/or misunderstood their indirect language,...perhaps responded in a non-helpful way,...and then beat myself up with thoughts of,
"I could have handled that interaction better."
I went for over 50 years relatively oblivious,...and frustrated,...and confused. Just with the past few years,...with active learning,...with being self-aware,...I am becoming a better person. I am a work in process, even after all these years.
@Oren Franz, what you are experiencing is not uncommon.