Regret is not the same as disappointment. Yes, regret involves disappointment and remorse, but also agency - What did I do, and what should I have done differently? I shouldn't have severed those ties, I shouldn't have compromised my personal morals... But what do we do with that energy? The Torah tells us that if we toil in that position of uncertainty, we would die in despair. However, the Torah then says, "But here's a way out." Acknowledge the mistake, say you'll do it different next time, and mean it. It's hard to look back over the last two years and not feel regret, but as we fully reopen and embrace each other as a community, we now have a golden opportunity to reflect and grow.