I really don't think about all this often, because it doesn't do any good to worry needlessly about it. But if I had to choose an option, I'd choose that I just want the war in THE UKRAINE to end, no matter who wins it. Does anyone know that about thirty percent of Ukrainians speak Russian? That THE Ukraine contains a city that till recently we called KI-ev (as in Chicken Kiev), not Keev. The Ukraine (which we called it till recently) is a border region, and has been pretty hotly contested for centuries. It contains the city of Chernobyl, for instance. The country has been ruled by the Poles, the Lithuanians, the Austrians, and the Russians. In 1919, the country changed hands five times in one year. 44 percent of Crimeans did not vote to leave Russia. In 2014 the President of the Ukraine fled to Russia and gave a press conference from Russia. He was replaced by another President, and then another one and then another one. I can't keep it all straight, nor do I want to, frankly. All I know is that the Crimea (in eastern Ukraine) is hotly contested. Is it part of Russia or part of Ukraine? Honestly, I have no idea and I am not qualified to pass judgment on it.
It's a long and complicated history, to be sure. And yes, it's true that the territory changed hands multiple times. The Mongols, Tatars, and Turks also had a presence in the region. A sizable percentage of Crimea's population are descended from Crimean Tatars. Crimea also became a flashpoint for conflict between Russia and the West, as Britain and France feared the possibility of Russia gaining strength in the Mediterranean region (just as the British had fears about the Berlin to Baghdad railway which would have increased German influence in the Middle East and Persian Gulf).
At one point in the distant past, the people known as "Ukrainians" and "Russians" were a singular nationality. They diverged culturally and linguistically as they became politically separated when Ukraine fell under the Polish-Lithuanian Commonwealth. That government didn't even call them "Ukrainians," but "Ruthenians" instead, a term which was applied to all Eastern Slavic groups. Another key difference is that the Poles and Lithuanians were Roman Catholic, while the Ruthenians were Eastern Orthodox. As the Polish-Lithuanian Commonwealth weakened, the Russians slowly and incrementally got back the Eastern Slavic territories they once held. Similarly, Russia started to push Turkey out of the southern part of Ukraine and in the Caucasus region, as the Turkish Empire was similarly in decline. I don't think anyone back then would have seen it as the Russians conquering Ukraine, since they would have seen the Eastern Slavs as their own people under foreign occupation by Poles, Lithuanians, and Turks, who didn't really belong there either.
While both Ukraine and Crimea were eventually within the fold of the Russian Empire, they were always considered separate territories. Ukraine made a bid for independence after the 1917 Revolution, but that was not to be. If they had, then Crimea and Donbas region probably would not have been part of it. The current configuration of the border was set during the Soviet period, when the Ukrainian Soviet Socialist Republic was formed. Crimea was added in the 1950s. When all of the Soviet Republics seceded and the USSR dissolved, a treaty was subsequently signed in which the boundaries were agreed upon based on their current location.
Now, it seems the Russians have changed their minds, and they no longer recognize those borders. That's pretty much welshing on the deal, so now they've launched an aggressive invasion which is a violation of even more treaties, including the UN Charter.
Russia was also concerned about former Soviet Republics and former Warsaw Pact states joining NATO in the 1990s and early 2000s, considering that an encroachment upon their territory and national interests. I've also heard that the US bombing of Belgrade in 1999 also led to a shift in public opinion about the West.
Of course, none of this would justify anything the Russians are doing now. They're clearly in the wrong, but we also have to consider the possibility of a shift in the balance of power in the world. Those who see the West as weak, divided, and decadent may try to gain advantage where they can. We are already facing sharp political rifts here at home over a variety of issues.