Why is enemy mmr always higher than mine?

ive legit searched op.gg before every single ranked ive played and ive NEVER had an enemy team with lower average mmr than mine. i only lose games. there is no way that i can win in ranked, the enemy always just wins everywhere. i get thresh on my team with wits end and nashors tooth ect. I just wonder why i never can be on the ENEMY team? why cant i have that ww jungle going 20kills, instead of having a yi farming jungle going 1/5 in the beginning...? I know that this sounds like crying cause of a few loses but this has LEGIT been the entire season now, enemy mmr always higher with players with more playtime than my team.