It's not a problem for the west. They don't give it away, not because they have nothing, but because they are afraid of WWIII. America has enough weapons in the desert for three such wars. With fifty old F15s or two dozen F35s, they could end the war in two months.On paper, Russia can theoretically can conquer Ukraine according to the ORBAT and manpower superiority.
In reality, Russia is deeply limited by political rules of engagement. It's political expediency to launch of a war of limited scope/objectives and refrain (until now) hitting infrastructure/civilian targets. When you are fighting with one-arm tied behind your back...you get limited results like this.
Yes NATO aid will continue, but @plawolf's point is the magnitude of aid will be attenuated or reduced commensurate with the intensity of war, to the extent that Ukraine major combat offensive operation is untenable, ergo a stalemate where Ukraine is unable to mount an offense, and Russia signalling the maximum extent of territorial expansion.
Yes, a unilateral declared end is one-sided, and yes, Ukraine can continue their offensive, but at best it would a stalemate along the Donestk-Zapo-Kherson-Luhansk boundary with no significant movement with reduced NATO support. This would be a bet on Europe reducing it's aid to Ukraine due to economics, inflation, and energy pressures, and end of S.M.O. impetus to give a blank check. It would be a risk-benefit analysis by Europe on giving an extra $66B per year forever just to grab Donbass, or just force Ukraine to negotiate a settlement.
Personally, Europe might be dumb enough to offer a blank check to Ukraine forever...they could be just that a stupid, at cost of hyperinflation, collapse of industry, recession, and their own people freezing to death. Their idiocy is limitless.
And you have to prepare for the real options, not the sucked up ones. That is why they are talking about negotiations, which can end with a stable situation, which means giving Russia the Crimea at most, and even stipulating the terms of return.