Now, like other such despots who over reach, Putin and Russia face military failure, economic and industrial decline, and a weakening grip on power. It is unlikely to end cleanly or well for Putin and Russia. Putin will be ousted in some manner and his regime of gangsters and crooks ended in favor of a new democratic order.
Ukraine is unlikely to relent in that US and NATO support continues and a full victory is increasingly possible, with Russia ejected from all occupied territories, including Crimea. Western diplomats and planners are no doubt figuring out how to accomplish that, force Russia into reducing her nuclear arsenal, and impose reparations on Russia in order to finance Ukraine's rebuilding.
I think the 1st part of that may occur, the latter is very iffy. It would likely take trauma similar to what Japan suffered in WW2 to change Russia's foundations, and with Japan we had the advantage of a still revered Emperor willing to work with us...
As for a Ukrainian "full victory", I think that to do it in under 5 years our level of weapons support must go up a lot. How do we supply enough HIMARS, for example, when the munitions (rockets) mfgr. is still studying* how to ramp up production less than 100%, and major orders are coming in, from Poland, for one...?
*I'd have never believed that had I not heard it right out of the CEO's mouth a few days ago! :-(
Russia will go nuclear should the above become likely.