My mother turned up a quote she thought was UK Prime Minister Winston Churchill, but appears to be from American author Arthur Somers Roche: “Worry is a thin stream of fear trickling through the mind. If encouraged, it cuts a channel into which all other thoughts are drained.” (I note that several variants use “anxiety” instead of “worry”.)
Of course Churchill is infinitely quotable and did have one on the topic of worry that sounds much more like his style.
And of course, there is the ever-popular… Don’t worry, Be happy.
Worry doesn’t get me anywhere. Decide what to do, and let go of the rest of it.