Pakistan's relationship with the United States has long defied easy categorization—too important to abandon, too frustrating to fully trust, swinging between tactical alliance and barely concealed mutual suspicion depending on the pressures of the moment.

The metaphor of a rocky romantic partnership has been applied by analysts on both sides: each party convinced they are giving more than they receive, each quick to dramatize grievances, each unable to walk away despite repeated disappointments.

The Abbottabad raid in May 2011—in which U.S. Navy SEALs killed Osama bin Laden on Pakistani soil without informing Islamabad—represented a defining rupture. Pakistan's military establishment was furious, humiliated, and forced to answer uncomfortable questions about how the world's most wanted terrorist had lived for years in a compound near Pakistan's premier military academy. Washington was frustrated that Pakistani intelligence had apparently failed, or chosen not, to act on his presence.

The relationship survived, as it tends to, because both sides remain enmeshed in shared interests too complex to simply sever. Pakistan provides supply routes for Afghanistan operations. The United States provides billions in military and civilian aid. Neither can afford the alternative.

What the relationship resembles most is an arranged marriage between parties who share strategic interests but increasingly little else. The trust deficit has become structural. American officials speak of Pakistan in private with a frankness that never makes it into diplomatic communiqués. Pakistani officials have built a domestic political constituency around anti-Americanism that limits what any government can publicly agree to.

The neglected girlfriend metaphor captures something true: the drama, the grievance, the inability to leave.