Okay, time for me to play.
Thunder mentioned my personal favorite (although SF's dog is my favorite non-Medusa one).
Here's the entire story.
Him: maybe we should have an open marriage.
Me: umm, there are two problems with that. First, since I already know about OW, technically we do have an open marriage. Second, there are rules to this kind of arrangement. The cardinal rule is that you cannot get emotionally involved with someone.
(Silence and the MLC stare)
Him: well, maybe is just need to f*ck other people for awhile.
Me: otherr people or other person?
(More silence and more MLC stare).
Him: I thought it would just be a fling.
Me: this matters why since it's been going on for months?
(Still more silence and more MLC stare)
Him: I think you should sleep with other men, as long as his Pen!$ is smaller than me.
(Medusa stands with her jaw hanging thinking, did he really just say that?)
On another occasion when we were discussing why he refused to spend time with me:
Him: I can't do it. I don't want to feel like a two-timer.
Me: (hysterical laughter that I'm sure the entire neighborhood heard)
Him: please don't laugh at me.
Me: (trying not to laugh) okay, but you do understand how stupid that sounds, right?
Him: yes
Later in the same conversation
Him: I really wish we could all move to Utah.
Me: Nope. Won't work. The first wife doesn't like the one you consider the second wife.
Him: (a look of profound disappointment)
Other classics from my clown include the comment that my multiple orgasms were a distraction, that I'd lost so much weight I was boney, and that he no longer found me sexually attractive because I look like my dad (it only took 30 years for him to notice).
I also got "I love you hit its not enough" (whatever that means) and "I don't believe we are programmed to love only one person in our life".