MMR How it work ?

Why i ask that ? Sometime when i play good and i go up to g2-g1 Riot , Karma , Illuminati they all are against me and give in my team like silver players but not only once , all my games and this continue until i drop to g4-g5 .
Is this mmr an influence to give me bad team when i have a good mmr ?
Yesterday i got a team so funny i post soon on youtube it will go viral soon is imposible to feed like that and me not flaming not feeding try to keep it cool and just accept my mmr drop my elo drop etc.
Pls someone explain this mmr problem so i can keep play lol or quit .

MMR depends on how good you've been playing in the past overall,so if the game matches you with much lower divisions that means you deserve to get matched with them because you are more or less the same skills as them.
Anyway since you have lower divisions teammates you'll have lower divisions enemies as well,losing relatively high lp and gaining low lp makes sense,because since you are in a higher division it's supposed to be easier for you to win.
Don't fall in the "elo hell" mentality where it looks like your team always feeds,because if you count how many times your team feeds and how many times the enemies do and you win your lane almost every game,roaming,shotcalling etc.. you'll see that the enemy team feeds more than yours.
You should keep playing in any case since the season is about to end and you can keep playing for fun or to improve anyway.
Remember: being a higher division doesn't mean you're improving,it means you're already better than you were before,so improving causes climbing,not to opposite.
Good luck on the rift,hope this helped you.

Idk about your queue times but if youre facing 5+ minute queue times when playing at night you're very likely to get matched with lower mmr players.