Recovery often feels like fighting a battle nobody else can see. But for a growing number of people, an unexpected partner is helping them win it: a 1,200-pound horse. In a Norwegian study tracking young adults in substance abuse treatment, those who took part in horse-assisted therapy completed their program at more than three times the rate of those who didn’t — 56.9% versus just 14%. That’s not a small difference. It’s the kind of number that makes you stop and ask why.