Sometimes things go wrong. Sometimes, your man is going to make mistakes (and let's be honest, women make them, too). He's going to take the wrong decision, and it might hurt you and him emotionally, physically or financially. He's as human as you are, and every honest man will tell you they don't always get everything right, even when they try very hard to make it look like they know what they're doing.
During bad times, times of doubt or times of struggle, be there for him. Understand what's wrong and accept that he didn't mean to hurt you. If he's a good man, he already feels bad enough for whatever he did. If he's lost, if he's struggling, if he's down, then he doesn't need punishment. He needs a hand to hold.