I studied Russian intensively a long time ago and got pretty good at it. (Good enough to intercept and transcribe Russian military conversations over static-filled radio links. And to read most of the canon of great Russian literature for pleasure.)

For about the past year, I have been working on Ukrainian, not with any great discipline, but by watching Ukrainian entertainment subtitled into English or Russian, mostly on YouTube. There's a lot more available than you might think.

Understanding Ukrainian was really difficult at first, but I'm finding it easier and easier. And it really is a lovely language. This is probably silly, but I compare the difference between Russian and Ukrainian to the difference between Spanish and Portuguese. Spanish and Russian are both beautiful languages, crisp and rhythmic. But Ukrainian and Portuguese feature a certain soft melody missing from their larger cousin tongues.

Or at least that's how I experience it as a native English speaker.