Maybe it's a guy trying to find love but can't. So he'll get into a relationship and then realize (even if he doesn't consciously know it) that this girl isn't for him. So he stops caring and the girl leaves him and he feels disappointed that she wasn't the one. So he goes into deep sadness and even anger. This speeds up the 'selection process' and reduces the time he actually cares about the relationship so the who cycle keeps getting shorter (Hence speed of light).
Maybe it's a guy trying to find love but can't. So he'll get into a relationship and then realize (even if he doesn't consciously know it) that this girl isn't for him. So he stops caring and the girl leaves him and he feels disappointed that she wasn't the one. So he goes into deep sadness and even anger. This speeds up the 'selection process' and reduces the time he actually cares about the relationship so the who cycle keeps getting shorter (Hence speed of light).