if the shoe fits

if the shoe fits(, wear it)

If something (typically negative) applies to one, one should acknowledge it or accept responsibility or blame for it. I know you don't like being called unreliable, but if the shoes fits, wear it. A: "Why do teachers always treat me like some kind of troublemaker?" B: "If the shoe fits...."
See also: if, shoe, wear
Farlex Dictionary of Idioms.

If the shoe fits(, wear it).

Prov. An unflattering remark applies to you, so you should accept it. (Slightly rude.) Fred: Hey, Jill, how's your love life? Jill: I don't like busy-bodies, Fred. Fred: Are you calling me a busybody? Jane: If the shoe fits, wear it. Ellen: The professor told me I don't write well! Bill: If the shoe fits, Ellen.
See also: fit, if, shoe
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs.

if the shoe fits

AMERICAN
You say if the shoe fits when you are telling someone that unpleasant remarks which have been made about them are probably true or fair. `She said something about me being in a bad mood,' — `Well, if the shoe fits.' Note: The usual British expression is if the cap fits.
See also: fit, if, shoe
Collins COBUILD Idioms Dictionary, 3rd ed.

if the shoe fits, wear it

If something applies to you, accept it. This expression is a version of an older term, if the cap fits, put it on, which originally meant a fool’s cap and dates from the early eighteenth century. This version is rarely heard today. Its replacement by a shoe probably came about owing to the increased popularity of the Cinderella story, and indeed, an early appearance in print, in Clyde Fitch’s play The Climbers (1901), states, “If the slipper fits.”
See also: if, shoe, wear
The Dictionary of Clichés by Christine Ammer
See also:
  • (one) could use (something)
  • drive (one) out of office
  • force (one) out of office
  • force out of office
  • give (one) (one's) head
  • give head
  • give somebody their head
  • give someone their head
  • cooking for one
  • as one door closes, another one opens
References in periodicals archive
If the shoe fits: A flamenco dancer with Russian ballet training, Anna, a member of Alma Flamenca Dance Company, looks for freedom of movement.
See Personal You, June 1995, "If the Shoe Fits ...").
"If the shoe fits," Kaplan says, "there is no need for the drawstring." When buying from a catalog, make an outline of your foot to send along with your order.