I think I have kinda grown out of such existential dread, once I started having a sort of intuition that the Universe is too inconceivably large to be uniformly altered, let alone "damaged", by any single event or entity (which also makes me cringe at sci-fi which throws the word "universe" around so lightly.)
More importantly, I started thinking of the "backdrop" of Reality itself to not be Nothingness, but Everythingness.
That is, the blackness we see out there, must not be the default state. I imagine a flood of "white" behind the void, and the reality we perceive is just a heavily-filtered slice of it.
What led me to this way of looking at things was a comment on HN or Reddit, that talked about how, in certain axioms of mathematics, you can have a null/empty set but it's impossible to have a set which contains everything including itself. Whereas in another group of rules, it's impossible to have an empty set because everything else is arrived at by "subtracting" from the "infinite" set!
Maybe someone here knows better of what I'm referring to.
In terms of darkness and hopelessness, this is getting close to Cixin Liu's The Three-Body Problem trilogy.
A rot13 spoiler follows.
V xabj V fgvyy unir cnatf bs rkvfgragvny qernq nsgre gur frpbaq be guveq obbx vagebqhprq gur pbaprcg bs qvzrafvbany erqhpgvba jrncbaf. Onfvpnyyl, n fhcrejrncba gung fgnegf n furrg bs 2Q fcnpr rkcnaqvat ng yvtug fcrrq, juvpu erqhprf rirelguvat vg gbhpurf, vapyhqvat fcnpr vgfrys, gb 2Q. Vg'f bar bs znal JZQf ninvynoyr gb cbjreshy fcrpvrf. Abj gur qnex guvat vf, vg pna'g or fgbccrq. Bapr hayrnfurq, vg'yy xrrc rkcnaqvat ng yvtugfcrrq, qr-qvzrafvbavat fcnpr sberire. Ohg fcrrq bs yvtug vf fb fybj, gung lbh pna qebc vg ng lbhe rarzl'f ubzr flfgrz naq abg pner nobhg vg sbe zvyyravnf.
Nsgre gung, sbyybjf gur dhrfgvba. Unir lbh rire jbaqrerq jul jr yvir va 3Q fcnpr naq abg, fnl, 12Q? Gung'f jul.