[CaptainBubba]

This isnt entirely related but I guess could be, since you could totally apply it here:

Whenever anyone (including girlfriend) talks about anyone who I

a. don't give a fuck about
b. don't know
c. hate

I just say this:

1) Yea... I dated (him/her/it)
2) (He/She/It) did (something gross or otherwise undesireable) so I had to quit it
3) ...but not before I hit it.
4) *wink*

Step 2 is the fun part guys, enjoy.