You never have to type

You just don't. You don't have to tell your teammate that he's worthless scum or that he deserves to get some terminal disease and die. You actually don't, like there is no prerequisite for that in your dna. You make that choice and you will face the consequences of that choice. At the end of the day, flaming makes you more of a burden than your feeding teammate.

Have you ever lost lane?

Do you know how shitty that feels?

Then it must be exactly how shitty they're feeling. So why make that worse? What's the logic in perpetuating and push them further into tilt? There isn't any and that's why it's a stupid thing to do. Trust me, nothing feels worse than feeding and getting flamed. I can handle feeding myself, but if someone is flaming me too then I almost feel obligated to argue back.

You see, I was in a very similar situation last game. I was doing pretty decently mid 5/2 and my ADC wasn't much good. The guy kept facechecking areas, chasing fed enemies and positioning horrendously. Top lane lost complete control over his lane and everyone just kept running into the enemy team like Tyler 1 on a bad day.

Of course I was pissed off and tilted, but I never typed a malicious word in chat. I did so because I did not need to type anything. It's not worth the effort, it's not worth the time and it's not worth arguing over. If you actually have anger issues I'd advise using a stress ball, punching your bed, screaming into a pillow or you can try listening to music. Take a break after every game or two, it'll help out tremendously.

TL:DR : Flaming is a waste of time, effort and energy so don't do it.

Best of luck and merry Christmas boards