I understand that the idea of draining vs. charging works for some people, but I always found this concept even more baffling. For me, when I've been in solitude for a while, I feel a restless desire to go out and interact with people. When I'm in that lonely state, I find social interaction "charging" and further solitude "draining."
But when I go interact with people for a long time—especially in a large group where I don't know people well—I feel an urge to retreat to solitude.
So am I charged by solitude and drained by interaction, or the other way around? It feels like the answer is "both"... so what am I supposed to do with all this?
One way you could think about my model is that you have four "batteries", each of which has an optimal "charge level." If you're under that level, you'll feel a desire to be in that state for a while. If you're over it, you'll feel an aversion to being in that state. And it's possible that if you're quite introverted, your optimal level of large-group interaction is close to zero.
If you're somewhere in the middle like me, though, the simple idea that you're "drained" by one thing or the other feels off.