Take one thing in consideration: Russia's government had only two options when ukrainian government were overthrown. Either annex as much territory as it can, or give everything up and wait until "peaceful protesters" will demand exclusion of Russian military garrison and naval base in key strategic point. Not to mention of any opposition.
Now Ukraine trying to enforce blockade on Crimea, and exploit any weakness or disagreements on peninsula.
Donbass is whole other story. It is tied to Russia industrially, and this bond is very strong. Like they build a lot of relatively cheap and quality heavy industrial parts and machines that can be sold only in Russia. Really. Not even in Poland and other eastern Europe. So, aside from all imaginary, or not so imaginary ideological threats from new government to people of eastern Ukraine, there is a HUGE economical treat for them if relationship with Russia become worse.
Worst thing that new ukrainian gov. is antagonising Russia economically from start, that was the main idea of "euromaidan" And without any suitable replacements for markets in Russia, Donbass would suffer greatly. Maybe even more than now.