Mature choices accept the cost instead of pretending every path can be kept.

Maturity here looks like paying rather than negotiating. You choose, you accept what the choice forecloses, and you stop running the alternative in the background as a comparison that spoils the thing you have. Keeping every path alive in your imagination is what makes any real path feel thin.

When you next decide something significant, close the other doors deliberately. Give the chosen thing your full attention rather than half of it and half a running audit of what else could have been.