Responsibility

If you don't want to heavy burden of responsibility, stop getting older.  With every birthday you celebrate more bills, greater expectations and more life changing decisions, like whether to move to Amsterdam or become a banker.  If you don't want to get older, you can either die or adopt a drug problem which freezes your mental development, neither of which is very fun.

Just keep in mind, carrying a mortgage is better than carrying the stigma of being an immature 43 year old.