Almost every cell in your body gets replaced over the years. You’re allowed to replace a few habits too.

Continuity is not the same as being fixed. You are already a different physical arrangement than you were a decade ago, and the sense of being one unchanging person is a story memory tells rather than a fact about your material. Nothing about you is committed to staying the way it currently is.

Pick one habit you have described as just how you are and treat it as a setting instead of a trait. Change the conditions around it rather than arguing with yourself about willpower. Give it a month, and let the version of you that emerges count as legitimate.