I'm very surprised that no-one else has posted anything similar to my reasoning. I sleep on the right of my lady, for a very simple reason:
It puts her between me and the alarm clock.
I'm totally useless at getting up in the morning, so she sleeps furthest from the door/closest to the table with the alarm clock on it. The alarm will wake her up, then she wakes me up!
I have been known on many occasions to not only sleep through the alarm, but to roll over and turn it fully off (i.e. not just snooze) without waking at all. We now have two alarm clocks, one at the far end of the room, and a radio too...
Pure logisitics!
