I have trouble with slaughterhouse stuff too. Just give it some time, it can be really confronting and you don't HAVE to read it. Doing so can cause burn out, so you're making the right choice to take a break.
While I absolutely do understand what you mean, by trying to bring about change by focussing on the humans, unfortunately some of the things animals have done to them have been brought about because it's 'better' for the humans. Tail docking in the dairy industry is done because the constant movement of the tails, annoys the humans who are fixing the machines up to the udders of the cows. Branding of animals is done so that the humans can tell who they own. A lot of stuff is actually done in the name of convenience for humans already.
Though, I think pointing to the fact that abattoir workers are more likely to abuse alcohol and be violent in their homes is a good starting point. I mean, these people wouldn't have to kill animals if other people didn't eat them, right?