What are the reasons for the collapse of the anti-Hitler coalition?

It is worth noting that initially the members of the anti-Hitler coalition did not consider each other as loyal allies for a long time. The main reason was the disagreement in the political sphere: the Western countries frankly did not like the USSR, as well as the USSR could not calmly coexist with the capitalist ones. This is confirmed by the very tense relations between these countries before the Second World War. The second reason can be called the desire of the countries in the anti-Hitler coalition “to grab a bigger piece for themselves” after the war. All countries considered the freed ones as their future puppets and did not want to share them.