This war only ends one of two ways. Either Putin dies (or is thrown from office, preferably from a 3rd story window, but that seems unlikely) or Ukraine gets pushed into such a bad position that they feel no option but to negotiate and cede territory.
Most wars do not end like WWII, with an absolute victory and a defeated enemy, most end with some sort of muddle. Clearly Putin isn’t going to get the entire country as he originally intended, but it’s conceivable to me that he ends up with some slivers of land so he can shout “Victory” back on Fox News, I’m sorry, Pravda (easy thing to confuse). If that happens I hope Ukraine followed a scorched earth policy and leaves absolutely nothing behind: no rail lines, no factories, no people, poisoned rivers, and dead Russians.
If they lose a couple hundred square miles, well, it’s a big country and they can wait until they are part of NATO which should stop further Russian aggression, and perhaps lead to a later negotiation in which things get back to status quo.