Hello Oak!
I guess in the modern sense of "egotistical", but more precise, based on things I have noticed.
If a rational, dispassionate 3rd party saw my situation and knew my stated goals, and they strongly suggested I take a specific course or stopped a specific habitual action - and I <didn't> take their advice, it could be for one of two reasons: either it is I just can't because of a disorder, or because of ego. Ego, where the rubber meets the road, is all about self-harmful rigidity in the service of a superficially self-serving false narrative about myself.
For example, another lie I would tell myself was "I am going to succeed to such a degree that everyone I ever met will be forced to have a positive view of me", and I would avoid doing anything that might burst that lie. I wouldn't get help (getting help would be a sign that I was broken), and I would reject any minor good and hold out for only home-runs.
Someday I would like to write a little book about all the things that really helped me through all the different challenges that I faced and continue to face. But I have no illusions that such a book could help someone who was a young version of myself to quickly and completely fix their life. Because ego would stop them from being able to take the advice - only as time eroded away the ego, could they find the freedom to take action to help themselves. If I wrote such a book, a big part of it would concern being careful with the ego - being compassionate but firm as the book guides through the stripping away at the ego.