Fear. Specifically, fear that I would walk away from that kind of income forever and that I could become destitute in the future (I have a weird relationship with money, having grown up rather poor).
I have read your comments about income, spending patterns and dreams about a simple life in the Mediterranean.
You've played the money game smartly and won. You just don't seem to realise that yet. You've described fear of poverty instead.
Can I respectfully suggest you to consider seeing a good psychotherapist if that's not yet the case? A therapist can help you conquer your fear. Please do read my suggestion in the friendly way I wrote it!
Fear. Specifically, fear that I would walk away from that kind of income forever and that I could become destitute in the future (I have a weird relationship with money, having grown up rather poor).