Antonyms for the phrase "accept gladly" include "decline hesitantly," "reject stubbornly," and "refuse reluctantly." These words suggest an unwillingness or hesitancy to accept something, whether due to personal preferences, beliefs, or limitations. Someone who declines hesitantly may be interested in the offer, but unsure if they can commit. To reject stubbornly implies a sense of defiance or conviction against the offer. Those who refuse reluctantly may be hesitant to disappoint the offeror, but ultimately feel unable or unwilling to accept. While accepting gladly suggests eagerness and enthusiasm, the antonyms show a range of reasons for declining, each with its own unique nuance.