What is up with the matchmaking lately?

I've been going through back and forth win streaks and lose streaks this season. Some losing games I 1v9 and still not manage to win because all my laners are feeding and on my win streaks I don't even try and the games just wins itself.

On my lose streaks I've noticed that my teammates are very uncoordinated and completely lack game sense that even when I'm tracking the enemy jungler perfectly and spotting them with wards they still get ganked. On my win streaks however I don't even need to ping my teammates, they are very coordinated and proactive around the map. The games are always one sided, its either us stomping the enemy team or us getting stomped.