Soldato
I'm not so sure. For decades the EU has happily traded with Russia, to the benefit of all concerned. There was even talk of Russia joining Nato back in the early 2000's. Personally I think this has more to do with Putin (and close associates) utterly deluded belief in Russia's (read Soviet Unions) place in the world. A strong trading relationship between the EU and Russia strenghens both parties. A possiblity which is probably now gone for at least a generation.
The talk of Russia joining NATO was only in one place, Russia
No one else even considered it that I know of