Up front, I've been drinking which doesn't help my rhetorical skills and got into it with my lib friend about Ukraine et al. It was a long conversation that ultimately went around in circles, but the jist of it was that on my end, we should not endlessly prop up the meat grinder of Ukraine as it serves nothing but the western imperialist project. On his end, the argument was that Putin is a maniac and that nato should not appease him in his crusade to restore the Soviet Union. He came from an upbringing of UK champagne socialists and seems to have settle on lib nihilism as his pathway through life.
I'm not sure what I'm seeking from this post, but I guess, how do you all deal with the conflict of people that you love desperately clinging to the horrid power structures that replicate the horror of the modern world? I've been pretty blasé about the results of the US election, because the dictatorship of the bourgeoisie will continue on its course regardless, but it's really hurt that someone I care about deeply has taken the "you're a tankie, you must love le pootin" position against me. 
I hate that wanting something better for humanity is the madness rune. I guess I'm just deeply sad, and I love you all so much because without all of you here I would only be left thinking that I must be mad for hoping for something better.
The answer is difficult but simple. Stop trying to change everyone’s opinion, because you won’t.
Unless your friend has political power, there is no point in trying to change their mind beyond honest and unashamed expression of your own opinion. By openly debating with someone whose mind is not open, you work to close them off further. It makes your views seem desperate for support; only tentatively reasonable, therefore easy to dismiss.
Socialism is inherently righteous. It does not need to beg for acceptance. The truth of anti-imperial, anticapitalist politics is sustained empirically and based in scientific theory. Bourgeois political theories come and go with the rise and fall of bourgeois interests.
Your friend likely will never change their mind. But they might one day, through life experience, gain some curiosity about it. Only at that moment is there an opening, and instead of fire-hosing leftist theory at them, they will ask earnestly for information. Onboarding only works if it’s a mutual desire.