Are you happy when others are happy? Or,  do you like the crab mentality thing? Or, you just want to remind yourself a hundred times that you are sad? That, you don't want others happy? Ooh, how sad is that?! Unless, if you are that of the first sentence of this paragraph.

Now, comprehend, examine yourself if you are this person or what. For sure, there's that good in you, that one day you twist your understanding that it's really great of being happy of what other's makes them happy. It really makes a huge difference if you do that.

Why? Think of your own happiness. There is always a jealousy attitude I know, but when you start telling yourself that you should not do that, instead, tell yourself you are happy about it. Promise, you feel at ease of yourself. Take it from me, mark my word. Do it, not later but now (and see the difference)!