"They're more like sparring partners."

Today I went on an outing to complete the dreaded Christmas present purchases with my lovely ex-boyfriend and his even more lovely mother.  (Yes, I am aware this sounds odd.  So what.)  We got in the car,  me in the front and his mom in the back (she sees the front seat as the death seat, I am not really rude) and persisted to bicker about everything.  As always.  It's all in jest but we can't help ourselves.  It goes a bit like this:

C (him): "Oh look.  There's a bird of prey."
L (me): "What kind of bird of prey?"
C: "I don't know."
L: "Why not?"
C: "Because then I'd be some kind of loser bird enthusiast and you wouldn't be my friend."
L: "I'd be your friend if you were a bird loser."
C: "No you wouldn't."
L: "Why not."
C: "Because you wouldn't."
E (his mom): "Do you know where your going?"
C: "Yes."
L: "Sure?"
C: "Yes."
L: "It's cold."
C: "No it's not."
...later on...
E: "You two are like an old married couple."
L: No we're not.  Are we? (Worried!)
C: Nah, course not.
L: That's alright then.

The only problem with this is I think his mom is right.  Later, when meeting one of his aunts for the first time, the question was raised: "Is this Chris' girlfriend?"  His mother's response could not have been more brilliant.  "No, they argue too much for her to be his girlfriend, they're more like sparring partners."  Whilst essentially correct I always though the fact our argumental sides could keep up with each other was a good thing...not one to be the reason we weren't together.  Oh well.  Never mind.  Bring on the sparring.