Speaking about this. I have this problem lately. Managing Man Utd. Sold off Lukaku, a day before the first game vs Arsenal. Drew a lot. Win a match or two. Then lost a lot too. Players all in good mood but the squad couldn't score to win, mainly because my main striker has left. It almost made me want to reload and play again. But I endured it massively.
Eventually, my young striker finally stepped up, entering the new year.
My point is - sometimes i think the game wants to put you through this period and then it will slowly come up again. In the past, I will reload and replay until I win, win and win to gain that confidence back.
This time, I just endured and finally I get back my winning streak. But of course, I didn't win the league that season. Ended up Number 3 w Spurs won the league under Pep.