Putin was going to invade in either case. He didn't invade because Ukraine was courting NATO, he invaded because things were looking up for Ukraine and Russia has been languishing for a couple decades now and he didn't want an up and coming democracy beside him, he wanted a Soviet style puppet state than he could dominate. It also gives him an excuse to push foreign countries out of Russia so he can tighten his fist around the throats of Russians even tighter and blame it on the West