you can have the entire shared armrest to yourself,but stop elbowing me

[hejhej]

Really pisses me off, I hate the things. Is it too much to just have some personal space and not be constantly elbowed?

Are you on a plane or train?

OF course YANBU, unless you're planning to sit there, silently seething. Say something! "Excuse me, you keep elbowing me, I'm sure by accident, but it is quite uncomfortable. Please can you stop."

Nyeah.
DH does this to me all the time. While I'm driving. It's not a small car either, but I elbow him back.
Perhaps a "arm rests are never big enough for two, are they?" comment may suffice?