I have to laugh at folks who blame their <50% win rate on RNG of the MM. If win rate were purely based on the randomness of the MM, then wouldnt' everyone's win rate be between 49.9% and 50.1%? Just remember that the only consistent feature of all your dysfunctional relationships is you...the only consistent feature on the teams that have produced your 55% loss rate is you!
This coming from a player with a lousy win rate, but I know that is my own fault.