Appeasement has never ever worked.
It has never worked in the past, and certainly won't work now.
Putin sees diplomacy as weakness, he will not even consider to the table until his army is broken beyond repair and the operation has all but died in name.
Russia are currently recruiting homeless people and convicts from prisons as cannon fodder to be used in Ukraine. Promising to erase the prison sentences of those signing up - which is a good deal for the Kremlin, as it is doubtful those convicts will ever be going back to Russia alive, so it will save money as well given the fiscal situation. It does however highlight just how desperate the 'operation' has become, when all thoughts of replacing fallen soldiers turn to the homeless, and so we can not expect to see a slicker and renewed operation from Russia anytime soon. Indeed Ukraine are now winning back fallen towns and cities, and they are motivated to fight to the end. They have nothing to lose unlike Putin.
We can not stave off Putin by throwing him scraps of Ukraine, in some vain hope he will stop and be happy with his slice. Even the most basic understanding of psychology will indicate that this man will stop at nothing to achieve his aims and goals. He won't sit back and be content with the Donbas, that is wishful thinking. Nor will it make the rest of Europe any safer.
Depleting the military assets of Russia, stripping their army bare, and reducing them to nothing more than a tattered rag tag army (which we are fast approaching) is the only way forward. Anything else will be simply kicking the can down the road.
The alliance you speak of with Iran and China etc, this alliance has been around for years. It is interesting that China have resolutely stood back from this war, refusing to get involved. And why would they wish to be linked to such a failure and disaster? China only cares for one thing: China and its own interests. Russia have not done themselves any favours.
Ukraine can reach it is own conclusions, and decide its own fate. It is now steaming ahead and I wish them all the success in the world reclaiming their country.
You sound like a Jeremy Corybyn apologist vera through and through. Appeasement with dictators never works. History is littered with similar mistakes.
Our pensions and mental health will be the very least of our worries if Putin is allowed to win.