why is it that I always loose in ranked?

I know I am sucky when it comes to ranked but I want to do better. I don't have very many friends that are online all the time to do a party but when I do its alright. Just wish I didn't run into a troll or toxic player every game, I'm trying to atleast climb to silver but what I've noticed is when I play ranked it's differ't I cant just do average on a ranked game like id o in normal and the fact that I'm trying to get better and not improving much scares me yeah I can practice in normal but that's not the point I want to be able to play ranked and be good without getting yelled at every game because of one mistake and then screwing up some more because all my team is doing si being pissed at me. I tried playing warwick jungle for the first time in ranked don't usually play that role in ranked . I've played jungle in normal but ranked I screwed up so bad and I felt bad because I fucked the game up for my team even though they were toxic I still wish I could of done better. Makes me feel like a noob when I play ranked to be honest and it sucks.