Sorry let me clarify it is the selection tool that seems to be not workig right. This is Version 10.
You accidentally hit command H the shortcut for View.Show/Hide Edge
Hit it again you will be fine.
View | Show/Hide Bounding Box
Ctrl+Shift+B on a Windows machine, Cmd+Shift+B on a Mac.
Actually I am thinking of something else it the Bounding box.