You didn't get what I meant, lemme explain. See the world map and you will notice, in the east, Japan and South Korea have presence of US military, In the West (around central west more accurately), Turkey is a part of the NATO alliance and so is Poland in the West of Ukraine which also borders it. Now imagine how a country would feel being sorrounded by its worst enemy from all the sides, this would have had definitely become the case if Ukraine joined NATO if its biggest enemy, it is totally unacceptable and this is the exact reason of Russian aggression towards Ukraine. The thing is, Russia is deliberately not trying to end or win this war. If Russia captures all of Ukraine, then Poland and Romania will become its immediate neighbours who are already a part of the NATO. The problem would still remain the same. If Russia stops the war then Ukraine will immediately join NATO which it is not able to do now as NATO does not makes countries already engaged in war a part of it. The goal is to keep NATO away from immediate Russian neigborhood.

The best thing Russia can do is prolong the war to the extent which Ukraine cannot afford it, establish a puppet goverenment and leave, Ukraine in such a case would work as a wall between Russia and NATO.