lifelong

abiding, enduring, persistent, persisting

bred-in-the-bone, confirmed, deep, deep-rooted, deep-seated, entrenched (also intrenched), hard-core, inveterate, rooted, settled

firm, fixed, frozen, hard, hard-and-fast, immutable, irradicable, set, unalterable, unchangeable

embedded (also imbedded), implanted, inculcated, instilled

inborn, inbred, ingrained (also engrained), inherent, innate, integral, intrinsic, natural

accustomed, chronic, customary, habitual, regular, typical, usual