Why are people bullying me?

So uh, recently I got cyberbullied by a graves and a lee sin. They were just sending hate messages to me about how I was feeding so bad and my teammates took my kills, but they were just like oh wow what a excuse. They were just being really mean and so i took action, i fought back but said some bad things I shouldn't have honestly, it was also my 3rd time using yasuo, and they got really mad at me and also told me to stop breathing, stop playing the game, uninstall and, and just overall kill myself. I said some bad things like you are a retard, you're cancer, i realize that, that was a mistake and I shouldn't have said that, but I only defended myself, and then when i stopped typing because i didn't want to go against toxic people anymore, my whole god dang team started cyberbullying to..., so now I don't know if its okay for me to play league or not anymore, what should I do? Also this is just another account to test champions to decide if I should buy them on my main, I don't even know if that's okay because i can't find it anywhere and I know a lot of people doing that to, so if it's not okay, just warn me please. (don't insta ban my account please if it's not okay to make other accounts to test champions). If those two are reading this by the way, please don't be as toxic to others as you did this day.