Every single game I play Unrated or Ranked there's always people who just one tap me and have a .000001 reaction time no matter how i peek them anywhere on the map. This is beyond frustrating because it feels like there's nothing I can do,...

Selfish gameplay is most likely the reason you are stuck. You probably do not want to hear it, and you mite even yell at your monitor in rage, but it is true. In a game where everyone is trading and looking to win every 1v1 without a moment...