Those who move the pieces are the powerful and the rich, while we (ordinary citizens) are just solitary gears in the machine of our countries, which we do not directly control.
Hostilities can be stopped, it has happen before and it can happen again, specially when war between nations harm the economy of those in charge of big corporations.
All we can do as citizens is to hope for the end of violence and raise people around us with love and understanding, so they can live without violence in their life.
Russia depleting their arsenal is a possibility but i am not sure if it could actually happen, the klemlin has China as a close ally in this conflict, at least in economical terms. Which would translated to China providing all the weapons they consider necessary for Putin to continue on this aggression. Ironically and considering what you just posted, I have seen news on TV on the possibility of Ukraine joining NATO as a full member.
Considering Russia wanted to weaken the NATO presence in Europe, now they are getting exactly the Opposite with the addition of the Scandinavian countries that wanted to join not long ago.