DnD, like many games, is a great method of distraction. It's hard to think about anything else when you're knee-deep in spell-casting with your buddies. All the woes of the outside world slip away when you're gathered around a table pretending to be a necromancer, bringing your comrade back to life so you can fight a dragon together. It's impossible to be stressed about your own life when you're stressed about completing a near-impossible puzzle that will unlock an important clue on your journey.
This is why we keep coming back. It absorbs us fully in a world that is not our own. It lets our imaginations run wild, and we can wield powers we never could in real life. We can go on impossible adventures and help make a (fake) world a better place. And then we get to look at memes about our beloved game. Does it get any better than that?