There's probably a reason Ukraine hasn't done a large-scale counter-attack, at least yet. Two reasons come to mind: Either they lack the strength, or they think they can sap the strength of the Russian forces by staying on the defense for a while longer, and only then counter-attack. Either way, if they were confident in their ability to counter-attack, they probably would, but for now, it seems to be either not possible or too risky. Russia may have screwed up, but attacking against them won't be as easy as defending against them.
If Russia can freeze the situation without Ukraine being able to dissolve the situation, that might just be close to the result of the war. At the moment, that would indicate Ukraine losing the rebelling areas as well the corridor between Crimea and Donbas, with Russia unable to force many of their other demands. Russia has already shifted its narrative on Donbas, and a land corridor to Crimea would be an additional benefit. Remarkably, this might also allow Putin to present the so-called 'special military operation' as a success on the home front. It would be an outcome that really sucks, but it's also one that might be the one we end up with unless Ukraine can muster the strength to drive out the Russian forces - which, like I said, is not at all guaranteed.
Additionally, while time may sort of be on Ukraine's side, if Putin can freeze the conflict, I doubt there's going to be very much opposition on the home front. On the other hand, it's Ukrainian land that's being devastated, so a prolonged conflict is not in Ukraine's best interests. Ukraine might have to bite the bullet and take some losses, while keeping its de facto independence in addition to its de jure independence (which was not really threatened at any point anyway).