Trolling/bullying

So I had a a game earlier where for the first time in a while someone said if they don't get mid they will intentional feed(this was norm Draft). And our sup just said he was going Top. So me and my friend were forced to go bot after picking our champs for mid and top(shen and Kat)(we thought they where joking). And when we didn't do well they flamed my friend for "picking" kat adc in all chat and saying they got mid and top fair and square. And when I called them out for lying about it they said I was flaming them the whole game(again in all chat) despite it being the first time I had used chat and I wasn't spam pinging(in fact they were).

This is definitely the worst case I have seen in my games recently but stuff like this seems to be happening more. not as bad as pre-dynamic queue levels but still concerning