Article in English: You are going to feel upset because of a rejection, whether it's having your manuscript rejected, an idea rejected at work, being rejected by a potential romantic partner. You are allowed to be upset about that, and, in fact, it's healthy for you to give yourself some time to process and grieve. Make sure that you don't go overboard and spend days sitting in your house wallowing in your misery. That will only make you feel worse in the long run. Now, this is not to say you get free rein to shout your pain about the rejection from the rooftops. This will only tell people (your potential publisher, that girl that you liked, your boss) that you're whiny and dramatic and can't handle life. So get a trusted friend/family member or two and talk it over with them.  The friend you want is the one who will tell it to you straight. They can help you sort out what went wrong (if anything; sometimes there aren't things you can change and you should just let it be). They can also make sure that you stay on track with your grieving period so that you don't start wallowing. Avoid getting on social media to air your grievances. The internet never forgets and when you're trying to get that fab new job, your employer might check the internet and see that you don't handle rejection well. No matter how upset or angry you are, just don't. Don't complain too much. Again, you don't want to wallow in the rejection, otherwise you're going to work yourself up into a state of righteous (or depressed) fervor. Don't start in about your rejection every time you're talking with your friend. If you think you've gone overboard, make sure to ask them "Am I dwelling on this rejection too much?" If they say yes, adjust accordingly. The earlier you accept the rejection and attempt to move on from it, the easier a time you're going to have. It will also mean that you won't let rejections in the future absolutely flatten you. For example: if you don't get that job you were really hoping for, allow the appropriate time to be upset and then let it...

Summary in Indonesian:
Jalani masa-masa yang mengecewakan. Bicaralah dengan teman yang bisa dipercaya. Terimalah penolakan dengan cepat. Jangan menganggap penolakan ditujukan untuk diri pribadi Anda. Lakukan kegiatan lain.