As one of my students proclaimed with excitement, "aha, so it needs energy to keep them apart, then when they stick together that energy is released!"
That would make sense, it would need more energy to keep things apart if they are more strongly attracted to each other.
To my embarrassment, somehow I never really questioned why bond making is exothermic during my education. It just seemed reasonable that it's the opposite of bond breaking which should be endothermic as it takes energy to pull things apart. I'm interested to read others' thoughts.