anal-retentive

obsessive

adamant, adamantine, bullheaded, dogged, hard, hardened, hardheaded, hard-nosed, headstrong, immovable, implacable, inconvincible, inflexible, intransigent, mulish, obdurate, obstinate, opinionated, ossified, pat, pertinacious, perverse, pigheaded, self-opinionated, self-willed, stiff-necked, stubborn, unbending, uncompromising, unrelenting, unyielding, willful (or wilful)

wayward, wrongheaded

determined, hell-bent, inexorable, persistent, relentless, resolved, set, single-minded, steadfast, stouthearted, tenacious, unflinching

firm, hard-line, hard-shell (or hard-shelled), iron, severe, stern, strict

hidebound, narrow-minded, rigid

bloody-minded [chiefly British], cantankerous

contrary, cussed

contumacious, disobedient, froward, insubordinate, intractable, recalcitrant, refractory, uncooperative, ungovernable, unmanageable, unruly

defiant, insurgent, mutinous

indomitable, invincible, unconquerable

confirmed, inveterate, unregenerate

demanding, exacting