Well yes Russia is aiming for marathon - it has no other options. Originally plan was to crush Ukraine in a couple of months and install pro Russian government and finish it - did not go well.
Statement that Russian losses are not so big are based on what? Russian side is hiding their losses even more compared to Ukraine. Neither losses of people nor equipment are public. You hide numbers when they are not good, nothing to speculate there, Ukraine is doing that - but Russia too, it is the same reason for acting like that - both have huge losses.
Regarding NATO - that organization is dinosaurs from another era. It is not functional nor it has clear purpose or strength for some time now. Nor it is really dangerous to Russia - for years. We see that some countries in NATO are quite big supporters of Russia (Hungary, Turkey). We see that some non NATO countries are more involved in support to Ukraine like Sweden. We see that some East European countries like Poland, Romania and Baltics do not give a dam to NATO - they know organization is not functional. Only security guarantee for them can be given by US, not NATO. So NATO is only cover story for official Russia, like it is some mythical monster that is supposed to destroy Russia. But it can not even produce enough ammunition for its own defense let alone to support Ukraine lol. So no, NATO is not real reason for this war; if anything this war clearly clarified that and exposed all weaknesses of NATO publicly.
That was the plan, and indeed it would have been delivered upon were it not for NATO going all in on this conflict, promising Kiev unlimited arms, resources, mercenary support, and keeping its employees paid and state structures functioning artificially through virtual money infusions.
But since NATO did go all in, so now the battle is against NATO. There's a reason why the later is refusing to back down and ready to engage in nuclear war rather than lose in the Ukraine.
Russia's job is to manage these threats, work to split the alliance, prevent escalation, and neutralize all enemy units on Ukrainian territory, though in such a way so as to preserve its own manpower and its own defenses in case NATO does decide to send expeditionary forces.
For Ukraine it was always issue that it was too close geographically and culturally to Russia, so NATO was never able seriously to bridge that gap and incorporate it into its own structures. But Russia was not able to crush that country in time window of few months. Now west has to respond. Ukraine still has many restrictions on strategic weaponry that has longer ranges, more payload etc... but as war continues those restrictions will melt too. Again it was up to Russia to do quickly the job and make a peace - it did not happen. No one in Kyiv will ever again listen to what Moscow has to say. For them - Russia crossed line of no return.
The West was always going to respond and was responding from before the war. That indeed was the whole reason they did everything to provoke Russia into a war. Several new military bases of Britain and the US were opening. Yaroriv was training 1-2 bridages of Ukrainian troops a year. Western mercs and arms supplies flooded into the country well in advance of the Russian invasion.
True, they thought that Russia would be able to occupy east and central Ukraine rapidly, and that they would move into western Ukraine while organizing an insurgency in the part of the Ukraine held by Russia. And that this would basically work, especially as the economic sanctions would be biting Russia and increasing domestic unrest there and thus tolerance for casualties.
Russia decided upon a different strategy. One that increases the strain on NATO arms supplies while keeping Russia closer to its own borders, but at the cost of having to face a larger Ukrainian mobilization pool and having artillery and missiles be close enough to threaten its own territory.
As for the line of no return - well once again, they were willing to discuss terms in March and April. It was NATO (Washington more accurately) which interfered in the discussions, per the Turks, former Israeli PM and Jeffrey Sachs; they all claimed the same thing.
But let's say they're not willing to discuss terms from now on. Well sucks to be them. I'm fairly confident someone will crop up in the end though. Right now the kool-aid of imminent Russian defeat and isolation is still wearing off.
You are not serious, it is good to have balanced and sometime opposing views, talking with people that all have the same opinion is boring in my eyes.
I have no problem with that but then come up with something original, as otherwise it seems we're rehashing the same discussion over and over and over again.