Game not feeling as fun

I have been playing this game sense early 2013, and after all these years, i have thought this game to be one of the best things to ever happen in my life, i remember coming home from school and thinking: Finally, i get to go league! However sense season 8 it all seemed to drift apart. I was always a regular player but not a very competitive one, i remember playing as assassins and just oneshotting my oponnents or going support and doing a game changing ultimate. I started to go play more competitively sense the end of last season, i thought well almost 5 years of playing this game will surely get me into a good rank! Me and my Jhin were just dominating the games all the way from unranked to silver 2 (#lowelostruggles) but getting all those wins and losses felt exciting and every match was different, although i've lost multiple games because of my team, i usually went into the replay mode to check how i could win the laning phase more with Jhin.

Season 8 starts:

oooooh boyy was i excited i went home and for the first couple of months me and my jhin and other pocket picks adc's where just doing amazing, until it got to a few months back, my fun from learning the game and experiencing matches just vanished. I feel like every match plays out the same now and although it was like this for a long time, the fact that all the players are playing so well just make me feel sad. I get it that games must evolve, but im on silver 2 how come everyone is so coordenated? My jhin even though he is one of the strongest characters on bot lane as of right now, i just don't seem to be having fun on that role anymore, everytime i try to go another lane beside it i just get demolished sense it was a role i've been trying to perfect for such a long time. Now assassins seem completely pointless, every game, doesn't matter how long, no one from the enemy team seperates at silver 2 this is a role i previously thought i could surpass with quite alot of ease, i just get dominated over and over again, and as of right now i don't know what to do with the game's evolution, everyone is starting to slowly know how to play better and better and as of right now i just can't handle anything of the new season the meta, the players etc

Not to mention most of the times i win early to mid game and i just stomp but as soon as it gets to late game i might be winning 32-3 but we manage to loose because of 1 fight and i don't know what to do