Has anyone ever told you "It's not you, it's me?"?

At which point they should be reminded that adults supposedly are capable of growth and recognizing that they should not become seriously involved if all they are after is sexual release. If they want something more, they must be prepared to deliver that. If they are unable to do so, they should wear a sign that says "Will screw but won't commit!"

Everyone has heard this one and, of course, you're right. It IS them. It's a cop-out and something that you might hear right before they head out the door. It's a diversion that they hope will keep you from looking at the real reason they're not involving themselves more in a friendship or relationship (not necessarily another person), sometimes fear of commitment. Haven't heard nor used your response, but it would sure leave them with their mouth hanging open! Another option, when someone says, "It's not you, it's me" is to say, "You know, it really IS you, and you need to get some therapy before you mess up another relationship."

Yeah, I've heard that before, and I've always answered back by slugging the hell out of him. If they fall then they're guilty and it really was them heh!

No. They always point the finger at me, especially when they float monstrous air biscuit in public.

People these days can change English grammar & they can include the new phrases into grammar, like the example that you have.

my break-ups usually involved hand-to-hand combat and little talking so i really never got the "it's not you, it's me" routine... I would love to get it someday just to be able to give the George Costanza line back:

"You're giving me the 'It's not you, It's me' routine? I invented 'It's not you, it's me'. Nobody tells me it's them not me, If it's anybody, It's me!"

Oddly, no one has ever said that to me. But sadly, I have said it a few times. It's never true.

Yea. It happens to everyone at least once.

They say that when they can't think of any excuses

yup...and I have always said this: "well, then you probably need to figure out why you continue to lie to yourself."