I feel jealous of my depressed sister.  Am I in the wrong for doing so?
What makes you jealous of her?
I'm not sure, but I do know that jealousy is a dysfunctional emotion that brings out extreme negative thoughts
I see, but since you know so much about it you should know that jealousy isn't healthy. Both you and your sister need to work out your problems or see a psychiatrist, because it isn't healthy harboring such negative emotions every single day.
I feel good since I'm seeing all this negative emotions.
It's good you're able to recognize these negative emotions, but you probably shouldn't be enjoying them. If they are affecting you mentally I would recommend you talk to someone that could direct you to talking to a therapist. This will get you on track to fixing your mental health.