Unless and until any Ukrainian-fired missiles actually hit something important, like a city block or the Kremlin or something like that, the Russians will simply hit targets in Ukraine. Now, those targets may include foreign embassies at this point given Putin's statements - although embassies are generally supposed to be spared even in wartime, they can become legitimate targets if military activities are being conducted from them, something Putin could allege.

However, he's winning and has no interest in drawing NATO directly into the conflict prior to Trump coming into office. Ukraine is clearly trying to drag NATO in so that Trump's hands are tied, which is just ruining their chances of remaining a sovereign state when Trump comes in. Putin indicated he would discuss a cease fire with Trump, Zelensky just keeps parroting his tired lines about Russia needing to leave "all Ukrainian territory" (including Crimea) as a precondition.

You can see where this is going. Trump will say, "Ok, fine, fuck you" and cut off the funding for Zelensky if Zelensky sticks to his position. And he would be right to do so.

If Zelensky were smart, he would agree to almost anything to make Putin the recalcitrant party, but he's boxed himself into a corner domestically through previous stupid decisions so now he doesn't have that option.

It's likely the Ukrainian army will collapse in the next few months, which will lead to a quick surrender. The model here is World War I - a long war of attrition without serious movement, followed by a collapse.

How does Ukraine lose? Slowly at first, then all at once.

Of course, Trump might pull off some sort of miracle and end the war on terms that are better for Ukraine than total capitulation, but it requires Ukraine to actually be willing to give up a lot.