Sad, angry, jealous, and guilty feelings can make you a healthier person. Figuring out the reason for your negative emotions and learning from unpleasant experiences makes you stronger, and that success can bring happiness- but when you suppress and ignore negative emotions, you eliminate the balance of good and bad. Because the contrast of feeling sad is what makes feeling happy so wonderful, happiness wouldn’t really exist if you’d never truly embraced your sadness. Source Source 2 Source 3