Well this has already been causing conflict with Russia for decades. Of course, keeping Ukraine totally neutral would be the best option, rather than assuming Ukraine is part of America's sphere of influence.
How is Ukraine supposed to stay "neutral" between Russia and the West when Russia is occupying parts of it and constantly threatening to occupy the rest of it?
It’s not, but neither is the West obligated to assist it when it is obviously not in the interest of the West to do so.
All of "the West" do not necessarily share the same interests.
And even if we limit the West to the US and the bigger states in Western Europe it's not that obvious. Both the US, UK and France (along with Russia and China) guaranteed the sovereignty and territorial integrity of Ukraine in return for them giving up their nukes. Letting Russia steal Crimea was bad enough, but nuclear proliferation will soon get out of control if Ukraine is forced so cede big chunks of the east and south, core areas of their state. That's more dangerous long term than the risk of Russia going nuclear in a regional conflict with NATO.
