I'm not Russian, just someone who tries to look at the issue from all different perspectives.

"Supporting democracy" in itself isn't a problem, but when your actions directly benefit you and weaken your enemy, your motivations are called into question. This is much like being at the scene of the murder of someone whom you truly hate and whose death directly benefits you. Even if you were there for benign reasons, you are still a suspect.

The overthrow of the Yanukovych government and its subsequent replacement by a Pro-West government falls in line with Western economic, political, and military interests in the region. In addition to increasing trade with Europe and the US and securing access to local natural resources, Ukraine's entrance into the European Union will strengthen Europe's political and economic power, particularly that of its more influential nations (namely Germany, France, and the UK). The expansion of NATO (which Ukraine has show great interest in) also gives the West a military upper edge over Russia by providing them with a direct border with the country.* Just a few years ago, the US attempted to install a missile system on the Polish-Russian border. Russia now has reasons to believe the US might do that with the Ukrainian-Russian border, which naturally presents a threat to Moscow. In short, these events have shifted the geopolitical center of Europe by realigning a Russian ally with the West. The West's actions thus feel like some type of international lobbying (to the Russians at least).

There's also no significant reason to believe Ukraine will become more democratic or developed through a closer relationship with the West. Governments from both the Pro-Russia side and the Pro-EU side have taken power before and offered very little difference. Corruption is rampant and Ukraine is effectively ruled by oligarchs. Fighting over which group of oligarchs should rule only results in death and destruction. Entrance into the EU has hardly improved democracy, freedom, and development in nations such as Bulgaria and Romania, it is foolish to think it will be helpful to Ukraine. In the end, this is a game of spheres of influence between the West and Russia. Whichever side wins, the Ukrainian population loses.

^{*Poland and the Baltics also share a border with Russia, however they are nowhere near as strategic as Ukraine. The Baltics represent a small geographic area that could easily be overrun by Russian forces, while Poland borders an exclave.}