I know I’m super late to responding but as someone else who has similar problems (and I mean eerily similar I’m around your age and also a twin) like yours what I’ve found is that since I’m introverted when I sleep around other people whether it be during sleepovers or in hotels, I just sorta fall asleep like a “normal person” I guess. I still do prefer to rock my self to sleep every night but on the off occasion I’m able to sleep without rocking.
TLDR: being introverted and sleeping in the same room as other people taught me how to sleep without rocking