I keep stalling at the midpoint of my novel — how do you push through the sagging middle?

The saggy middle is almost always a symptom, not the disease. Two usual causes. First, the middle sags when the stakes stop rising — if your character is just doing things rather than being forced into harder and harder choices, the reader (and you) drift. A reliable fix is to hit the midpoint with a real reversal: a win that turns into a bigger problem, or a truth that changes what the goal even is. Second, sometimes you stall because a decision you made earlier is quietly wrong and your instinct knows it before you do. When I'm stuck I ask "what would make this worse for the character right now?" and write that. Also, practically: stop editing while drafting the middle. A lot of midpoint stalls are really perfectionism disguised as plot trouble — give yourself permission to write it badly and fix it later.