Need help in ranked

Ive hit plat this season at a 65 percent winrate because i played past gold seeing how far i can get. I get to plat 3 and ive had 12 game loss streaks all the way down to plat 5 0 lp. And then ill win some lose somes grind back up to plat 3 and just lose 12 more ganes in a row, and now im at 51 percent winrate. In every game i lose its not even close. My games feel like a 1 sided stomp. Even in games where i am popping off getting 20 kills plus i lose, i also feel like when i spam camp lanes my laners still always lose 1v1 to the enemy and its boggling, im not saying i dont ever feed. I can prolly say 4 outta 20 games are soley my fault we lost. Im kind of just looking for advance to the next level. I play just about any role with jungle being my main roll and if i get tilted ill switch to w.e role i want to play.