Is it normal that i hate letting other people borrow my pen?
Right, often they never give it back. It slips their mind, it slips my mind. Or things are in a rush. Or it's a group signing a card for someone, "May I borrow your pen?" Goodbye, pen!
Or if it's a fountain pen. I'm afraid they're going to bear down on it too hard and wreck the nib.
Or worse yet, they borrow the pen, use it, and I see them mindlessly putting the pen in their own pocket. "Excuse me, my pen please?" And then they're like I'm some sort of jerk for speaking up and not letting them make off with my pen.