There is an old fable about red ants and black ants in a bottle. The two ant types co-exist peacefully in the bottle. There are no problems. Then someone violently shakes the bottle. The red ants and the black ants get agitated, and go at each other. The fight continues until one side is destroyed.
As I see it, that’s not a bad analogy for the current Ukraine/Russia situation.
The “coexist” idea was IMO always a surface thing, Putin has written and spoken negatively about Ukraine and it’s very existence, the bottle was shaken as you say at the very least in 2014 and very little happened, Putin also shook the Georgian and Chechnya bottle as well, and very little happened.
So it is not surprising to me that Putin made the decision to invade. Combination of his desires and I imagine a huge dose of bad intel he was given on the state of his military and expected Ukrainians world response.
Putin crossed a line and for him and possibly the Russian federation their very continued existence is at stake.
I see no scenario where Putin declared victory and withdrawals. If he does he is gone, if he doesn’t Russia dives deeper into third world status
Just my 2 cents