Why does copper not react with nitrogen?
Sketching with broad strokes: the first key point is that oxygen and nitrogen are major components of the atmosphere in the form of $\ce{O2}$ and $\ce{N2}$ molecules, and not as ions. $\ce{N2}$ is a very stable compound because the two nitrogen atoms in its molecules are united by a particularly strong triple bond. $\ce{O2}$ is overall more reactive than $\ce{N2}$, largely as a reflex of the bond between the atoms not being as strong. Specifically concerning oxidation reactions (of which those you suggest are typical examples), oxygen atoms having more affinity for electrons than nitrogen atoms contributes towards making $\ce{O2}$ being a better oxidiser than $\ce{N2}$.