Anne Garréta, from her 1986 novel Sphinx:
“How often did I imagine myself gripped with terror, collapsing, tumbling from the height of the relative safety of whatever promontory I had been occupying? A fall brought about by the purely internal and continually foreseen rending, imminently suspended on a final thread that never broke but which, taut and twisted unbearably, never ceased to tremble. The agonizing tension of always being about to crack without ever feeling the relief of chaos—for I denied myself even the obscene plenitude of annihilation.”
The universality of this sentiment to anyone who has struggled with the “mental dismal” is striking, but aside from this fact I took two things away: first, don’t be afraid of long sentences. Second, look up plenitude and use it regularly.