My wife wants to be hugged and held all the time, me I don't like hugging or being held, I find the covers restrictive and the room too warm, I sleep with half my body out in the cold. But, I like to hug sometimes. I like to be touched sometimes.
I don't think your sister has any real issues, it's just how we are, I need my private space, so at night when everyone else is asleep I sit here either typing random replies or playing games. I worry over things and work out how to do other things and think of random ways to fix or break random things. Everyone needs their little bit of space, has thier little dislikes and pet hates. It's really not something to worry about.
Some people might say she wasn't loved enough, or loved too much, or embarressed when she was a kid with a hug or perhaps someone once caught her by surprise and now it tricks her mind when someone touches her there. But all of these things are little things. And not the kind of things to worry over.
Is that a ring in your lip? That gotta have hurt...I don't like jewelry...does that make me mad tho?