he's not "convincing himself" of anything. this feeling is a side effect of any number of things going on his life. don't jump to conclusions about someone.
Everything we believe is the result of us convincing ourselves of something. If you tell me the sky is green and I believe it, it's because I decided to believe the sky is green not because you told me it was green.
He believes his life is not luxurious. Someone with no relationship and no job could easily look at his life and see it as luxurious. Someone like Jeff Bezos could look at this guy and be like, "that's not luxurious at all."
This guy can change how he views his life and he might be better off for it.
Or he can hate his life and bemoan his circumstances. Up to him.
So you have a relationship, athletic hobbies, steady job, and side business?
That is luxury. It's just that you've convinced yourself it's prison for some reason.
> now I'm back to the same place I tried to escape back then, albeit in a different physical location and work place.
As they say, wherever you go, there you are.
Even if you found "luxury" then you'd convince yourself it wasn't enough.
Figure out how to solve that problem. Because quitting your job or whatever isn't going to work.
> I get scared when I realize that this is my life for the next 30-40 years.
If you get 30-40 more years of life, think about how lucky you'll be compared to the people who die of cancer in their 40s or 50s?