Just after validation or something more?

Long story short - a guy I’ve worked with for 5+ years is confusing. We were friends initially, super close would chat all day about each other relationships etc and hang out but after a couple years we had one night where we joked about sleeping together and how that would be and after I got home that night we ended up sexting and did the same a few times during the week.

We kinda parted ways at the end of that year as I was tired of being confused by him as we never got past Snapchat and that was tiresome for me. This was a few years ago but we still chat and in the last year he would randomly move over to Snapchat and start getting flirty and sending nudes etc.

Most confusingly, we’ve never touched anymore than jokingly holding hands. Even now whilst he’s being flirty on SC if I go anywhere near him he flinches and moves away! People at work have always thought we must’ve slept together cos of how we are with each other. Last year I kinda told him what annoyed me e. g. the fact i was clearly into him and he showed no interest and he just blamed it on being autistic and said he regretted not having a serious convo with me about it at the time. I’m in a happy relationship now but every time he is single or dating someone he’s not interested he comes back to me. I don’t want to ask him why as I know he’ll just make up some rubbish! Guys, your opinions please! Is he actually interested but autistic or does he just want Snapchat validation when he’s lonely?

Just after validation or something more?
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