Why I LOVE League of Legends, but i HATE the community

I just played a game of Shen with my friend on one computer and we were jungle, we go and help mid to avenge our Jhin but our friendly Tryndamere flashes in and presses e from over the wall, so we die to tower of course we get mad that he stole a kill that was already confirmed, later in the game we helped out some more because we were playing Shen so we kept dying so our team mates can live. friendly complaining banter I type something along the lines of I cant do any damage, squishy team kind of forced to go tank, this is when we learn they are a premade all in Skype, they start picking on us for K/D/A. Then I had lost it because they were blaming the fact I died for them the reason we lost and everything was my fault, so I typed in caps that I'm tired of this getting constantly abused by a premade because they aren't getting what they want. all they did was talk K/D/A and damage done that match. yes me and my friend were also being stubborn and salty because of the round but the premade wouldn't even take no as an answer. I honestly just wanted to rant about this game because it was so stupid to be matched with so many people who are together in one game which they all proceeded to report someone who tried helping the team but failed. I mean I love League of Legends but things like these make me feeling like selling my accounts and moving to another game community.