Experience Tumblr like never before
The thing is, if Mike had said in any other context ‘My life started November 7th 1983’ it would be understandable.
He could’ve meant that his life started because it was the first time he truly felt loss. Of course that loss being his best friend going missing and leading to a body being found.
It could have meant that his life turned upside down when he found out monsters and powers were real. The night his childhood became a cycle of pain and horror, with him and a gaggle of other children being in charge of saving the world. But his life didn’t start that night in the woods, his life started ‘that night he found El in the woods’. And I know it was supposed to be him professing his love or whatever, but El didn’t start his life. The Upside Down did, and Mike has the two confused.
I know it’s a bit nit picky but I think it’s fun to point out that it feels more like he’s projecting his feelings about the Upside Down onto El. He frames it as El being the catalyst of his life because at the time she symbolized the supernatural things happening in Hawkins and the hope of getting Will back. Because him finding El in the woods introduced the world that had consumed his life for the last 2 and a half years at the time of his monologue.
anyways Byler is canon