What does this mean? Why do you care about them so much? Why can't you stop caring about them?
Most Helpful Girl
That's love. It sucks but that's just how feelings work, even if you don't want them, you'll sometimes have them.
You don't have a switch to turn off your feelings, though that would come in handy quite some time.
Best thing is to try to cut contact with that person, get your own life back on track and try to forget him.