Compared to previous eras, we're actually far more peaceful than we've ever been. The difference is Mass Media tosses everything in your face at the exact moment it happens, so you realize shit's getting real on a simultaneous level. That, consequently, feels like a lot to take in. If you're being objective, though? Nothing's going on that even remotely qualifies as an "endgame" scenario.
That said, there's about two dozen "endgame" scenarios playing out every few weeks, if you listen to some of the more alarmist people and/or groups online. In my lifetime alone, I've seen the Order of the Solar Temple sect plan mass suicides, I've seen the pre- and post-Y2K software paranoia and I've seen the whole Mayan Apocalypse kerfuffle.
We're still around, and there's always going to be people ready to reinterpret Nostradamus' verses and basically go "Hey, we were wrong! The end of the world's not coming in two weeks, it's coming in two centuries!"
As to why, it's because this whole Doomsday stuff is arbitrary and depending on whether or not you're talking about the end of the world as defined in mythology or religion, or the end of the world as defined in terms of political and cultural ideologies.
Consider your concerns, for instance, and I'm sorry if I sound temporarily unsensitive, but really? Really?! Scotland and Ireland have nationalist groups, views and potential aims and that somehow threatens the UK?!
The cure for these fears is pretty simple. Look back to the past. You'll realize things have changed. The UK used to be a fairly small Medieval nation, the Enlightenment extended your reach, the Industrial Era saw Britain actually become the United Kingdom you're familiar with, at least in terms of nomenclature. It used to be far bigger than you're used to. Consider Hong Kong's fairly recent secession from the British Crown, for instance.
No country's borders or boundaries is ever set in stone. Things change over time, even if takes centuries. If Scotland were to secede, practically nothing would change. The region might lose some British tax breaks or post-tax collection windfalls, but going independent is something that needs to be planned, something that has to come with a set of contingencies. What would be left of the UK would have to plan as well, seeing as Scotland going bye-bye means less tax money in the country's pockets - at the trade-off of less people to support.
So are things really going to shit, politically? Not particularly. Today's wars are bloodier than ever, that much is true, but they're also shorter than ever. The point of war gets across faster than ever. That explains how the Kim dynasty's intimidation tactics don't scare anyone. Telling Washington you're going to go Hiroshima on its ass because it's being a poopyhead might have worked in the fifties. It absolutely won't work now.
Plus, consider your age. I'll assume you're fairly young - either as old as I am (I'm 31) or somewhat younger. You're smack-dab in the politics of *your* era, just as we all are in our respective age ranges. All that goes on obviously is going to feel pivotal and serious to you; but try bringing your concerns to someone who's lived through WWII, or even the nineties' kerfuffles with Iraq. You'll realize there's a ton of people out there who have seen the same, or even worse.
If you want to be philosophical about it, though, the world *is* ending. It ends every evening and restarts every morning. Every day is its own little thing, and someone's ordinary Cheddar Macaroni dinner evening is someone else's life-shattering or life-ending horrific set of circumstances. That can't be helped.
So... Live and let live. Control what you *can* realistically control, and that involves voting and making your voice heard. Past that, you have to live with the knowledge that there's just so much going on out there that you will *never* be able to fully grasp. Ever.
