I hear what you're saying and I'm the same age as you. The prospect of a nuclear war is terrifying, but I think the prospect of Russia winning and invading more countries on its border is even more so.
I'm a bit older, and well remember being shit scared at intervals as a teenager. I was at school in a garrison town fairly close to some major airbases, so it all felt rather real at times.
But... Since then I have become very familiar with the history of WWII. Appeasement doesn't work. Putin got away with far too much, and it made him overconfident, both of the abilities of his own forces, and of the willingness of the west to let him do as he pleased. He's hit those limits now, some would argue eight years late.
I've also just finished reading a book on the Gulag. Shitting hell. The attempts to decapitate nationalist movements in the Baltic states and the Ukraine, the sheer brutality and neglect and needless suffering. The KGB and its precursors were all caught up in this, and Putin, as we know, is a product of that august institution. It's no surprise that he's like he is, and he has to be stopped.
It's as depressing as hell when there are so many other major issues that need to be resolved.