Whenever I try getting into physics, I get depressed because of all the theories about the end of the universe. Stuff like entropy, ekpyrotic universe (where the universe can end any second), proton decay, etc. Sure, they might be a lonnnnng way off, but it's still inevitable which makes every thing right now seem so pointless because there's not even gonna be a single atom of trace that we even existed, like there isn't for possibly an infinite amount of civilizations in past universes that existed. It's just a pointless cycle. And then there's always the thought that you'll NEVER find the answers you're looking for when researching physics.