League's competitive environment is the most toxic and infuriating experience I've ever had

I've played this year for 7 years now and this is when I quit. Honestly I can't bear with this catastrophy of a competitive system, it is tearing me apart inside almost every time I play it. I am a very competitive person, I aim to be at the top of the ladder and I try to do everything in my power to reach it. But unfortunately this is not as easy as it may sound. Why? Because my games are not decided by my own performance, I only take up 20% of a game's outcome and it kills me. I hate when skill doesn't mean everything, and I have to rely on the RNG matchmaking system to find me decent teammates that won't lose the game for me. I previously thought that the further up you go the less toxicity there would be, and it would be easier to focus on carrying the game and try to grab objectives with your team. But I soon discovered that even in diamond everyone are just entitled brats that all think they are god's gift sent to the League community to carry people. My last game I had a support that decided to go roam because "our adc sucked" when he died during a turret dive to get the double kill. Even though we came out on top, this guy decided that his adc wasn't worthy of winning a game with him, and decides to go roam top lane at level 3. The top laner gets pissed then and immediately says "I'm afk" and that leaves me with an instant lose I have absolutely no control over. How does this define who's the best League player? How can I through skill, effort and knowledge win a game if I got even 1 guy who decides he doesn't want to win. It's just lost. There are so many factors that determines a game's win chances that you, the individual that wants to increase your individual ranking, can't do anything about. Things such as:

• Jungler performance
• Team getting fed or feeding
• Team's ability to group and be at the right place at the right time
• Teamfights
• Does the team grab objectives or not
• Team's choice of champions
• Team's choice of items
• Team's attitude

I've simply had it with this game, I'm throwing in the towel, there's nothing competitive about this game, there's no way to climb the ladder without having to succeed at RNG as your own skill level is only a fracture of what's required to win. And that kills me. If I had a friend that wanted to try playing League, I wouldn't recommend it really I'd infact tell him to not even bother, there's simply nothing but frustration coming out of that game. Nothing makes you feel more cheated of your effort when you lose because of something you could have done nothing about.

It's impossible to stay cool in this game, eventually you've just built up all this rage you've kept down from your losses and people making stupid mistakes, and it just ruins your entire day.

Anyways rant over. Have a nice day.