I totally understand that; however, on the flip side mental is so important in this game. If you are giving up after one bad fight, it sort of becomes a self fulfilling prophecy. A lot of the times, it is not in your hands at all. Nor should it be in a team based game. That does not make it any less frustrating. There are some psychological arguments that queueing while tilted will fetter performance as well.
Personally? I just stopped caring. I just try my best and focus on having fun regardless of what happens. I am a negative Nancy type and it does not always work, but it definitely can. I had fun in a game where my Sistah Spice and I were the only ones trying. I do not mean my three teammates were bad. They were literally throwing. They would emote in the middle of the battlefield and refuse to participate.
We still did great because we just kept playing and did not care about the result. Easier said than done because there was another game where they had a leaver which was a 5v4 in our favor and I SWEAR to the heaven’s above it felt like a 4v6 in their favor. It was soul crushing and I was triggered. No fun to be had there. It’s difficult to tap into that state of Zen.