The end seems to me that it will be the surrender of Ukraine and sit down to negotiate, Russia will keep the Donbass, Crimea and some surrounding areas... The West will never include Ukraine in NATO, western Ukraine will be divided between its neighbors, Poland and company (this part is fundamental for the West to pressure for a peace agreement) and this part would become part of NATO due to its inclusion in the territories of belonging states... in summary: Ukraine will only be a small part of territory that will divide NATO of Russian influence on the border

Just I'm smoking something 🚬 

 This seems very likely. Unless Joe really pushes back, then I think Russia will take the whole thing