Mine is when I totally ruined all my salary into gambling, that really made me feel I’m very irresponsible in my decision making that I let myself get caught with my gambling urge. But that also taught me about gambling the hard way, something that until now, I’m always reminded of it not to make wrong decisions again towards gambling.
Acceptance is the only key. Just embrace your mistakes and learned from it, that’s all. There’s no use blaming yourself, that will only lose your self-confidence. And from then on, I’m no longer getting attracted with betting all-in. That will only ruin my whole bankroll again.