They have been bombing and attacking Donbas since 2014. Wikipedia the war - it didn’t start in 2022.
Okay then. Ukraine for the Ukrainians, Donbas for the Dumbassians. Split the country with the Ukes on one side of a wall and Dumbassians on the other. A UN monitored referendum every decade to decide where the wall should be.
When oil was discovered in that region, it was Ukraine, so all the oil minus, say, 5% will be for the Ukraine.