By this point in your story, your MC has been through some ups and downs, but it’s about that time to kick your MC to the lowest point. It’s time for the protagonist to lose all hope and hit rock bottom.
In screenwriting, Blake Snyder calls this moment “The Dark Night of the Soul.” During this moment:
“The main character hits bottom, and wallows in hopelessness. […] Mourning the loss of what has ‘died’ – the dream, the goal, the mentor character, the love of your life, etc. But, you must fall completely before you can pick yourself back up and try again.”
Today, have your MC hit his/her lowest point. But don’t worry, things will get better for your protagonist from here on out.