It depends on what you mean by 'Britain' and what you mean by 'suffer'. It is quite complicated.
The British ruling class seemed to suffer a great deal. If you read David Kynaston's history of the City of London, the collapse post-Second World War, the reduction of the City (our Wall Street) to a domestic market, and the suspension of convertibility were all doom-laden events. Not like what happened at the end of the Third Reich, quite, because 'our' defeat was disguised as victory.
But then the centre of gravity of the post-war economy shifted from the colonies to Europe, so that Germany's and Italy's dramatic loss of Empire quickly turned into a blessing, while Britain's colonial possessions seemed to become a drain, rather than a source of wealth (so too for France). Of course, to survive the bleak years 45-48 the British 'sweated' the Empire brutally.
All through the post-war reconstruction, Britain lagged behind its continental rivals, which used to be discussed as the English disease (see Lamfalussy, Britain and the Six), largely because its empire had turned from an advantage to a drag.
Psychologically, the British ruling class had a persistent problem - which I am old enough to remember - that it had for many decades 'punched above its weight' politically. Its commitments to military roles in those parts of the world where they could play lieutenant to the US were important. But over time, the trend of decolonisation was one of persistent humiliation for the British ruling classes, who would go into spasms, like in Derry in 1972, or in the Falklands in 1982.
For the working class, there was a shift after the second world war. Reformism pre-war was largely as Lenin described it, imperialist super-profits channelled through state institutions to fund social welfare programmes, run by labour leaders. After the war, that persisted to some extent, but their was a stronger trend for wages to command more goods, leading to a US style consumer boom, which undermined the reformist machinery - largely for the better I would say.
Politically, the British working class movement's loyalty to imperalism was its Achilles heel. The trade union and Labour Party leadershup were vehemently hostile to anti-imperialist movements, particularly in Ireland (but also in Aden, Greece, Egypt, Malaysia, Kenya etc etc). And they were up until the mid-eighties, the driving force behind working class racism, operating all kinds of anti-immigrant schemes, 'last in, first out', segregated housing and so on.
For working people, I would say the end of empire was a great thing, and, notwithstanding the delterious influence of Labourist social chauvinism, I think most working class people would agree, the ordinary rank and file being much less enthusiastic about the occupation of northern Ireland's six counties, and generally much more liberal on matters of race.