I've seen memes and posters in a few places now (I've seen that image as a poster in real life) making the argument that "worrying" is never a good idea because it isn't necessary if you can solve your problem and it doesn't help if you can't solve your problem. This argument is so ludicrously bullshit I have to make an article ripping it apart.
Let me start with some comparisons to show that nobody actually believes this troll logic. My friend dies but there's no point in being sad because being sad won't bring him back to life.
Or: I'm being raped but there's no reason to get upset over it because if I can resist I don't need to and if I can't resist it won't help.
Emotions aren't a strategic action, dipshit. They're something called human nature. It's not even possible to choose not to worry when something isn't going the way you want, try it. You can no more choose not to feel self-centered negative emotions than you can choose not to feel pain, or choose to fall asleep at any moment you want.
Finally, worrying does help you solve your problem. It makes it easier to focus single-mindedly on what's important enough to make you worry and gives you an emotional impetus to solve the problem as well.
So don't listen to some trolls who tell you worrying is irrational because it doesn't help you solve problems.