I feel you. Actually it's the way mmr works. I'm a mechanically solid and constant player, my decision making is off sometimes but in general I'm pretty average, after my 3rd loss in a row I get tilted and stop playing for a bit. I can hold my own against plat and gold players on average. This season I got placed bronze 3, again. And it's tilting without end. My win loss ratio in normal games is 800 to 850, I started season 3, and since season 6, the difference between those two numbers is always around 50. I main support, mid and I've played a fair share of adc top and jungle games. However, it's come to the point that when I win 2 games in a row, the following game I get matched versus enemies who are simply far better than the ones I played against in the last 2 games, in fact after 2 wins in a row I can predict with a 90% certainty that in my third game the other team develops a game sense and a sense for map plays that is extremely uncharacteristic for bronze. Paired with the fact that for some unknown reason, people who play in my games just shit on any sense of team comps, I can with a 90% certainty say I do not win 3 games in a row. Basta. And after I lose the 3rd game, in my 4th game I get matched with the most insane scrubs this planet has seen, ending with one person getting so insanely fed that they simply solocarry the game. If I win the 4th game, the following games end like the 3rd. At some point however, my team turns and goes full god mode, completely roflstomping the enemy team, and I enter a cycle of getting outmacroed a few times then roflstomping. If I lose my 4th game, i enter the moderate cycle where it seems to depend on individual player skill, I may lose a bit but soon afterwards I win two more games in a row.
Now this is not about my win loss ratio, this is about the level of the players that I encounter. After winning 2 games in a row, the total mmr of the enemy team spikes insanely hard, sometimes up to 700 more than my team. This may not seem like a lot, but trust me at low elos it is. I clearly notice that I'm playing against a different level of players than usual. The problem is this: the lower your mmr falls, the lower the mmr of your teammates will be. Tbh, while I was just playing for fun unranked, the level of my matches was more constant and I actually had a higher winrate. After getting ranked bronze, shit went downhill hard. My buddies can confirm this, no matter what elo you are and how good you and I play the 3rd game, the 3rd game is a 90% loss, simply on the premise of getting outplayed on the map. It's like the gods of lol just decide to give the enemy team cosmic insight on the art of macro plays in the 3rd game, it's really funny sometimes. I can only explain it with mmr because that's the only number that I can see change by a hefty value