The problem of course is that Ukraine has no economic sovereignty already.
It is utterly dependent on Russian gas for its energy needs. Even if Yanukovich steps down, next leader will have the exact same problem - where to get gas to power the country and you can bet your last grivna that the price of gas will go ballistic if Ukraine is to do something, anything to jeopardize the security of Russian borders. For example, align themselves with the EU. They are in a check-mate :-|