Personal experience suggests:
You worry about the morning after before you’ve even started the night before.
You’ve gone through all your friends getting married and now start to see divorces loom.
You can have friends round to your house for drinks in an evening and not worry about things getting wrecked or your neighbours complaining.
A standard Saturday now involves a trip to B&Q, a nice coffee somewhere and some general pottering. And you’re not at all unhappy with that at all.
You have a drinks cupboard. And it’s not filled with crap, it has vintage Port, good wine and some carefully chosen spirits.
Edit.
And you finally sell your hardcore hardtail and buy a cargo bike with the proceeds.