end of one's rope/tether, at the/come to the

at the end of one's rope

 and at the end of one's tether
Fig. at the limits of one's endurance. I'm at the end of my rope! I just can't go on this way! These kids are driving me out of my mind. I'm at the end of my tether.
See also: end, of, rope
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs. © 2002 by The McGraw-Hill Companies, Inc.

at the end of (one's) rope

/tether
Out of energy or patience; exhausted or exasperated.
See also: end, of, rope
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

end of one's rope/tether, at the/come to the

To have exhausted one’s resources or abilities. The term alludes to a tethered (roped) animal that can graze only as far as the length of the rope permits. “Being run to the end of his Rope, as one that had no more Excuses to make,” wrote Sir John Chardin in 1686 (The Coronation of Solyman the Third). “I am at the end of my tether” was close to being a cliché by the time Royall Tyler used the line in his comedy The Contrast (first U.S. production in 1787).
See also: come, end, of, rope
The Dictionary of Clichés by Christine Ammer Copyright © 2013 by Christine Ammer
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