I'm not particularly interested in discoursing about this with someone who apparently believes the only legitimate expression of Ukrainian public opinion is anti-Russian despite the Maidan protests never even achieving majority support. But fine, here you go:
Ukraine quite literally was not Russia's puppet state and the United States saw fit to intervene in its politics anyway. Yanukovych wanted to join the EU, but the EU wanted to impose harsh economic restructuring (privatization/elimination of public services) that would have been very painful to the people of Ukraine on top of destroying Ukraine's trade with Russia. Of course, this is all more than a decade after the United States intervened in a Russian election for Boris Yeltsin who had three years earlier bombarded his own parliament with the support of the Clinton administration in order to prevent his impeachment.
The state of Russia today is largely the fault of the United States, both for its many provocations, unwillingness to engage diplomatically, and its great variety of direct and indirect manipulations (including the above), the handling of privatization (the birth of the much discussed oligarch class; that was done at the direction of the United States and its subservient international institutions) and so on. Similar dismantling and privatization was done in Ukraine, of course, which is why there is an oligarch class there as well. The transition to capitalism was a disaster for the entire former Soviet bloc from which they have not yet fully recovered, and still that was not enough for the United States which wants ever more with a hunger that can never be sated; they did the ideological thing and got a bunch of rich folk to dominate their society, but they're not OUR rich folk.
Francis Fukuyama's idea that the collapse of the Soviet Union meant "the end of history" is all the more laughable in the context of continued and escalating predatory behavior by the imperial core. We've got post-historical genocides going on.