Britain was bankrupt. Lend-Lease had become a euphemism in the latter stages of the war. American aid had kept the UK afloat and in the fight. The Island's people would go through some austere years after the War.
It was clear that after the emergency of the war India would have to be given independence.
The Boers were taking power and taking South Africa out of the British orbit.
Canada had developed a national identity during WWI and WWII. Canada would be a loyal ally but would no longer regard itself as part of an "empire."
The Brits held on a bit longer in Africa, but after the Kenya rebellion it was clear they did not have the resources to hold on there to what for the most part were money losing colonies.
The sun was setting on the British Empire.
Thanks for that cogent and helpful overview.
Nobody has studied this counter-factual history, nor made the case more cogently than Patrick Buchanan, whose book on it I have:
Buchanan 2008: "Churchill, Hitler, and the Unnecessary War -- How Britain Lost Its Empire and the West Lost the World"
Buchanan argues that had Britain made peace with Germany, it could have kept the Empire while Germany ruled Europe.
The world's dominant values would then be German imperial rather than American anti-colonial.
I don't agree with Buchanan on much, but if we are going to consider counter-factual hypotheses, his makes as much sense as any.