British people are very passive, so there's zero probability of any new pro-EU referendum. It's easier just to complain and carry on. Meanwhile, the EU wouldn't want the UK back, so there's zero reason to imagine that even a pro-EU result would make any meaningful difference. When a stupid little boy breaks his toy, you can't just glue everything back together and pretend nothing happened.
The British voted to commit national suicide in exchange for two mindless soundbites, and so they deserve all the calamity they get. Only morons would have voted for Brexit, and only morons did.