Match making questions and hopefully answers

I've been going through the boards looking for an answer but can't really find a straight forward one.

Back and forth from s2,s3 my teams consistently made up of silvers and below, while enemy teams consistently has 1-3 golds. I win some I lose some. What gives with the golds. I'm barely s2.

The high mmr argument makes some sense except for the fact that I'm only gaining and or losing 19-20 lp per game so my mmr can't be rediculous.

Honestly feels like the system is out to get you, but that's stupid right? I'm just a baddie that needs to get gud...