If a child pulls out his collection on a day when he’s experiencing a lot of pain, and then the pain stops, his brain “learns” that focusing on the collection stops pain. Each of us learns ways of stopping pain and turning on happy chemicals.
If you fail to empathize with shared pain, your social bonds are likely to be threatened. Your group-mates may start perceiving you as the threat. It’s not easy being a primate.
You feel bad at the thought of losing the life you have now, but you feel bad about losing the career advancement. Unhappy chemicals help your brain calculate your best option.