If I could just “opt out” of human society for like two weeks, I think I could detox.

I, too, thought the same thing. But emotional engagement and human connectivity is requisite for recovery and growth. In other words, you need to keep doing things and being around people. Otherwise you activate and reinforce the most powerful negative feedback mechanism of them all: isolation.

We are not the logical creatures we imagine ourselves to be. We are - ever and always - the emotional animal first. From an evolutionary perspective, the animal brain developed a long time ago, and things like logic and reasoning were only very recently stapled on top of existing structures. From a neurological perspective, the emotional centers of your brain are physically central. They activate first, and outer regions - like the prefrontal cortex - respond after. Often to rationalize whatever it is you just felt.

When you are down (not sad, but down) - perhaps from poor sleep, caffeine withdrawal, etc - your neurochemistry is out of balance. You don't just feel grumpy, or irritable - you are quite literally less capable of feeling happy or excited. It's not something you can think your way out of or power through. You don't have the right mix of serotonin and dopamine to pour a nice cocktail of happy, healthy emotional response.

Instead, you will often find cynicism and apathy. The logical brain is stapled on top, remember. If you don't feel happy or excited in response to a given experience, then logically, that experience does not make you happy or excited.

You can try to explain to yourself why. Perhaps the thing shouldn't make you happy. Perhaps it's just yet another shallow grasp at meaning in a meaningless world, and lesser things like that aren't meant to make someone like you happy. Perhaps it doesn't make anybody happy, and we're all just pretending?

If you notice, these thoughts don't do anything. You can't test them, you can't be moved by them. These thoughts don't have any way to improve your life or the world around you. They don't even have evidence behind them. They just go in a loop - I don't care -> why should I care? -> nobody should care -> nobody cares -> I don't care.

These 'rational' thoughts were triggered after the emotional response. You were apathetic before the experience, not because of it.

Maybe you're paying attention to yourself, being mindful. Listening to your body and your thoughts and your emotions. Maybe you can recognize that you're just tired, but that doesn't change how you feel. The dopamine doesn't rise, the serotonin doesn't release. Logically - rationally - stapled on top of the way you feel - is your consciousness, explaining to itself what is happening, and still unable to move the needle of your internal experience. The emotional animal brain is still first and foremost in control and it is not getting its rewards, so it will be even less likely to generate dopamine in pursuit of those experiences again, because it didn't work last time.

The solution is not to opt out of society, but to opt in. Find things that invigorate you. Embrace new ideas and experiences. You feel you have no time or energy - that the world is too fast and too exhausting to do anything but exist.

But the better you treat yourself, and the more you build of your life - the more exciting things that you plan and do for yourself and others - the more time and energy you will find.