Self-compassion is key. Forgive yourself for the things you didn't do, but also know that regret over inaction is just a feeling, and feelings are not perfectly

Self-compassion is key. Forgive yourself for the things you didn't do, but also know that regret over inaction is just a feeling, and feelings are not perfectly reliable. Regret is a heuristics informed by your values and perception. It can be good for you if you use it for good, just don't be entirely duped by it. There is no golden path, spending your twenties travelling the world or chasing a different career still could have led you to disappointment. Ultimately happiness can be learned, and can have little prerequisities if you learn to love yourself. I for example usually treat myself as a blob of fancy goo, I try, I fail, I forgive myself, I keep on trying. I try to accept that I can't control everything, I try to accept my limitations. Paradoxically once that happens, once there is no judgment the motivation to defend myself by entertaining delusions goes away and reality takes it's place. Only when I have a solid grasp on reality I can overcome my limitations.