Do something about MMR

I'm a Diamond V player with a really nice win ratio for my division, dare I say (59% in 200 games). Every single time I win I gain 16 lp but on each defeat I lose like 19-20lp. Basically the game is TRYING to force me down in ranking so I can hit 50% win ratio which is incredibly frustrating. I either get VERY good teammates or absolutely TERRIBLE ones and as a support main it's really sad to know that you can't do anything to help your team if they're plain TRASH. Sorry but it's the truth. Stop forcing people to stay in hellish divisions Riot for once, I skipped entire divisions in Platinum but your LP system is one of the worst examples of ladder ranking I've encountered.