The soviet definitions are completely different from the western ones.

Communism is a hypothetical social order, at which "people's well-being, equality and freedom will be
achieved on the basis of the highest development of material production, technologies and science".

Socialism is the first stage of Communism's development.

There were (and are) no communism countries on the Earth, but there were countries, which tried to achieve communism.

The sentence "The USSR is a communist country" can have 2 meanings:
1. Western: There is communism in the USSR.
2. Soviet: They develop communism in the USSR.

I don't think soviet people could describe the USSR as a communist country in the western meaning. They were teached that communism is the future, not the present.


What about the USSR collapse, I don't think it is related to communism in any way.
USSR never was independent from the Western Europe. In my opinion, the soviet governement was under control of the British Intelligence Service. The USSR was and Russia now is a British satellite.
The independent Russian politics was over, when the Russian Empire fell.