"Leave me in your mother"
Sharon, were you been smoking?
Arghh, "leave me in your mother"
Me: ahhh...Leave me in you mother
The error is built on similarity in the hebrew form of "swearing on", and "putting in".
The street slang often makes the speaker swear on his precious mother, as if to promis that he sais the truth.
In a same manner, it evolved so that when a speaker is replied, the replier puts the speakers' mother's sake on his request.
B: Ahhh, leave me, on your mother! I feel like shit.
A: Did you know that Miki sleeps with Michal?
B: Leave me, on your mother. Why should I care?
The "In your mother" is a shorthand for "in your mothers life" which is a phrase close in its meaning to something that is very precious and dear to you.
So I would translate it as "do me a very big favour (as big and important as your mothers life) and leave me alone".
He: Leave me, in your mother
Additionally, "In your mother" is short for "Swear in your mother", an Hebrew common to "Swear to god". Two-three decades ago, for example, the common was "swear to your most precious". "Swear to god" is not in use for obvious reasons.
The origin of that Hebrew phrase is probably "azov oti le-ma'an hashem!" which means "Leave me alone, for Christ / heavens sakes!"
From there it went certain changes to "azov oti be-shem elohim" (Leave me alone, in the name of god!). Because the last sentence obviously wishing that person to go away, it evolved into a less crule manner "azov oti be-ima shkca" - "Leave me in your mother".
This expression is useable whenever you don't have the patience for someone or for an idea.
Female: Leave me in your mother... I'm drunk.
Female: Hey babe! Wanna go shopping?
Male: Leave me in your mother... There's a game on TV.
Previous examples applies.