So are you claiming that Russia should be allowed to veto internal Ukrainian political decisions, or prevent them from voluntarily joining other alliances? Wouldn't it be better to just keep killing Russian soldiers until they run out and retreat?

Well they are trying that now. It looks like the tide of war is not on their side at the moment.

And yeah, you should've got by now that the position of your neihbours is the most important factor in the policy of most, if not all, countries.