I can't control my mind, and I always find worries starting to creep inside my head.
For example, my mother was diagnosed with breast cancer last week. It's very small and she says it treatable and not to worry. I wasn't worried at first, but then I thought more and more about it until I was terrified. I finally calmed down and felt great this morning, but now I can feel the worries creeping back in...and I can't stop them!

It's an awful feeling, like someone else is in control of my own mind. What can I do? Any tips?