How to return to the state of the winner?

I quit the game in June last year, it was 6500 mmr, in general there was a loss streak and I fell from 6800.

I thought about returning, but decided to end with the game. Then I came back in November last year, but I lost my mmr to 5700, I was in bad shape, I decided to play a smurf 3k mmr and raised it to 6k mmr in 2 months, but I'm still on some kind of tilt, I lost confidence in my forces

Maybe you had something like that after your lose streaks? How to deal with it? I feel like I can still beat these people, but I'm super insecure and stuff. I know that people like that annoy everyone, but I really don’t want to be pathetic, I want to return to the path of the winner, where I gnawed victory with my teeth.

it would be nice to hear some advice, maybe it's because I lost confidence while playing on smurf and now I don't play on main because of this?