Incorrect, the main goal is to prevent the current government mafia allied with government-connected industrial oligarchs in Donetsk region to become even less representative and even more Russian-controlled.
> I wonder if there are Russians living in the west part of Ukraine, how violently would the protestors deal with them.
So far the protests were targeting the government, not civilians. This is a very good thing.
> Because it seems that the protestors are driven by their hatred towards not-signing the deal with Russia instead of EU
Again, incorrect, the protests are driven by resentment against the current tightly-connected pro-Russian ruling elite.
> nazi supporters.
There is indeed a party with extremely right-wing views that regularly receives up to 8-10% of the vote. However it is questionable as to whether that portion of the population actually holds those beliefs or simply uses them as signaling to antagonize Russia.
> And the EU/USA always support the more radical parts of the society(with media, weapon support etc..)
Current Western support is nearly non-existent while that of Moscow is extremely significant and some would say heavy-weight.