That's simple. They're first of all Ukrainians, that's their national identity, and the fact they can speak Russian doesn't make them Russians. Once they all have realized that, there will be no need in the counter-terrorist operation, all the lands will be cleaned up by the locals. And who's going to endure losses will be whoever is investing in the separatism in the area now.
Why don't you think they can realize that they are not Ukrainians or Russians but the people of Donbass?