As for the "Britain has an army of millions of Indian-Zombie soldiers" people: This thought is so ridiculous that I am not even going to adress it.
Edit: And for the "Britain and the US could have raised a big enough army to defeat Germany even without the USSR" people: No they could not have. The maximum amount of troops Britain &Canada had in North-Western Europe by the end of the war was 1.1 million and the Americans had 2.6 million - and this number could NOT have been increased because:
In 1944, the United Kingdom was facing severe manpower shortages. By May 1944, it was estimated that the British Army's strength in December 1944 would be 100,000 less than it was at the end of 1943. Although casualties in the
Normandy Campaign, where the British Army's main effort of 1944 was, were actually lower than anticipated, losses from all causes were still higher than could be replaced.
In late 1944 a severe problem in the U.S. Army in general was the manpower shortage. Plans to expand the Army to 213 divisions were never met and it was proving difficult to maintain the 89 divisions then in existence - even though almost one-quarter of them had yet to see combat.
Intense combat and heavy losses in 1943 meant that in 1944 many divisions still in the United States were stripped of trained men to build up the replacement pool. Some divisions were stripped of available manpower a second time later in 1944. This in turn affected the training cycle of the divisions, causing some to deploy late and requiring most to have some problems with their initial combat deployment. Four armor, one airborne, and seventeen infantry divisions (nearly one-quarter of the total formed) were eventually subject to large scale stripping of men (nearly all of the other divisions in training also had smaller numbers of personnel stripped out prior to deployment). Fourteen of the seventeen infantry divisions were stripped twice.
https://www.ibiblio.org/hyperwar/USA/USA-E-Supreme/USA-E-Supreme-E.html
https://en.wikipedia.org/wiki/British_Army_during_the_Second_World_War
http://www.militaryhistoryonline.com/wwii/usarmy/manpower.aspx
https://www.ibiblio.org/hyperwar/USA/USA-E-Logistics2/USA-E-Logistics2-11.html
Counting the troops in Italy, then in 1945 Britain had 1.6 million and the US 3.2 men in the ETO = 5 million (rounded) To maintain this force level was allready proving extremely difficult and an increase would NOT have been possible especially considered much greater losses in NA in the 42-44+ period. This is 1 million less soldiers than the Soviets had in the 43-45 period as active soldiers on the German-Soviet front alone (6 million out of a total strenght of 12 million).
