One could argue, that fear of NATO made the Ukrainian war happen in the first place. Anyway, point still stands: We need more international unity, not less, since there is war in Europe, and the EU is arguably the closest tie between countries.
"Russian President Vladimir Putin warned that members of the Customs Union of Belarus, Kazakhstan and Russia may impose what he called protective measures in the event of trade liberalization between Ukraine and the EU. The EU condemned Russia's threats, calling them unacceptable. Ukrainian Prime Minister Mykola Azarov urged Russia "to accept the reality of Ukraine signing the EU agreement" and condemned any artificial barriers as pointless."
"After the economic part of the Ukraine–European Union Association Agreement was signed on 27 June 2014 (by the new President Petro Poroshenko) Russian President Vladimir Putin stated that making Ukraine choose between Russia and the EU would split the country in two."
Note that the military action taken by Russia started only a few months later, in November 2014: