Crimea is Ukraine. End of story.
Any "vote" there done without the authorization of Kyiv is illegal and not recognized by the civilized world.
Similarly, the referendums done in Eastern Ukraine illegally carried out by Russia, not Ukraine.
The people of the U.S. state of Maine might choose to join Canada in order to get nationalized health care, but unless such a vote were to be authorized by the U.S. government, it's political masturbation.
I get it that like the Hitler of our era Putin, you have no respect for the sovereign borders of nation states (might is right!). But sovereign nations will tend not to agree with that.