How do people not get angry at this kind of cancer?

I was 3/0/1 and I as on my way to gank mid (which I have not ganked and it was free). After I pinged I was coming my mid laner told me to "stfu" and then said "go away bitch". Completely unprovoked. How do people not become toxic when you have little shits that act like this? Honestly I said nothing (and for me this is a big deal, because I flip in game chat when people say this shit to me). I calmed down until my mid started talking shit to me later in the game even though we were crushing the other team and none of us died in that game, not one. So I flipped a little and said some shit and also said uninstall. How do you guys deal with this, im sorry but I do have some actual self respect to not let people talk shit to me unprovoked.

To prove how bad we were destroying them, we had a 20k gold lead at 20 minutes, so there is no reason to be acting aggressive towards team mates for no reason