There's this thing that happens...when you think about something for too long. It becomes the only thing you think about. It takes on a life of it's own. So what you need to do is take that thing - whether it be a person, an event, a job, whatever - take that thing and say. "F**k it!"
You can only be worried and thinking about it for so long. Take it and put it in a tiny box in your brain and forget about it. Trust that it will turn out for the best, or that you can whether the storm if that's what it becomes.
We only have so much control and so much say over the events in our lives and the actions of others.
I say that we choose to smile and let live.
That means let ourselves live and trust that those people/events will be as they should.