難分難解

难分难解
nánfēnnánjiě
to become caught up in an irresolvable situation (idiom)

CEDICT

  1. (of a romantic couple) to be intimate and inseparable
  2. to be intimate and inseparable
  3. to be locked in a stalemate in a fight or struggle

Wiktionary

  1. 彼此糾纏或爭吵激烈，不易分離排解。《初刻拍案驚奇．卷二九》：「賤的可以立貴；貧的可以立富。難分難解的冤仇，可以立消。」也作「難解難分」。
  2. 關係親密，情意極濃，難以分離。如：「他們兩個愛得難分難解，怎捨得片刻分離？」也作「難解難分」。

重編國語辭典

Entry Composition

1 難 nán
  1. difficult (to...)
  2. problem
  3. difficulty
  4. difficult
  5. not good
2 分 fēn
  1. to divide; to separate
  2. to distribute; to allocate
  3. to distinguish (good and bad)
  4. (bound form) branch of (an organization); sub- (as in 分局 fēnjú)
  5. fraction
  6. one tenth (of certain units)
  7. unit of length equivalent to 0.33 cm
  8. minute (unit of time)
  9. minute (angular measurement unit)
  10. a point (in sports or games)
  11. 0.01 yuan (unit of money)
3 難解 nánjiě
  1. hard to solve
  2. hard to dispel
  3. hard to understand
  4. hard to undo