Correct. The Ukrainians can eventually force Putin’s forces out IF they (the Ukrainians) can accept a 10:1 kill ratio in favor of Russia.
One must recall that the Ukraine lost 19% of its population in WW2, only to return to subjugation by Stalin. We cannot really even begin to imagine the scale of the horrors, or the “national memory”.
Tymoshenko sounds like she would do it (have Ukraine fight), but needs to be more forceful about eventually winning, which she does seem to be, as she recovers from her back problem.
I’ve also seen some writings from protesters praising opposition leaders they did not really like previously, because said leaders were willing to stand in there as the bullets started taking out protesters. If the Ukraine’s leaders show courage under fire, Putin’s guys are (eventually) toast.
Also... If Ukrainians start dying in large numbers, pressure to send in assistance will build.
This may turn out to be a squib, or it may be the Phoney War period, a time used by the Ukrainians to complete their mobilization. It's also possible that Ukraine's leaders are hoping that an Alamo-type event occurs in the Crimea. Putin is strenuously trying to avoid inflicting one on Ukraine, because he understands this could galvanize Ukrainian public opinion for a long war of attrition against Russia, which would end just like Russia's adventure in Afghanistan.