OP, you're lacking perspective, so here's some:
Manchester United and Liverpool are football clubs. Establishments that employ players and other people who go about playing the GAME of football. We HUMANS have been playing this game for a while now and people seem to enjoy it a lot all over the world. So we all started getting together to watch the best players compete at this game.
Liverpool FC is a football club. They're not terrorists. They didn't kill your family. They didn't bully you in school. They're just a bunch of people who got employed to either play or contribute in some other way in the GAME of football. They all worked very hard to get where they are, since there a hundreds of thousands of people who are trying to get to their place, and hence why they get paid a lot of money.
We all enjoy watching this game continuously, throughout the year, throughout our lives, but some of us (you) forget what it is. You seem to have forgotten what anything is actually.
Gary Neville, if you weren't aware, is just a guy. He sh*ts in the morning, eats junk food on occasion, watches p*rn, argues with his wife sometimes, and then goes to work where he talks about/to people about the GAME of football. He used to play it - he was famously good at it since he made it to a level where the majority of players never make it to. And now he talks about it.
He's never met you. He doesn't know who you are. He didn't mean to cause you to be upset. He's not even thinking about the reasons that you might be upset about. He's just living his life, same as you. He even, just like you, sometimes has a go at people (the whole Pogba instagram photo thing a couple weeks back) and looses his cool about petty things, so surely that could make you relate to him even more?
So please relax, take a bath or something. Eat some ice cream. Say something nice and warm to your wife/girlfriend/mother/friend/dog/a stranger. And quit posting negative rubbish. There's so much better things to occupy your mind with - like who to get for next week's Fantasy Premier League round, or how many ants live in the world - it's actually 10,000 trillion! Isn't that f*cking crazy!