Is life really about just working every day until you die?
No. The purpose of life in general is to propagate, to procreate and reproduce. "And you, be ye fruitful, and multiply; bring forth abundantly in the earth, and multiply therein." 9.7 Not that I'm particularly religious, but this is one instance where the confirmation bias nevertheless gets the right answer.
As for individuals, there's no purpose or reason, no subject of life. We make those things for ourselves, and it's truly an individual journey.
Why can't I function like a normal person?
Normalcy is a statistical concept, not a pragmatic one. Dazz almost nailed it. Normal people exist, but only normal in one concept. We can speak of normal height, or average height. But all people of, say, 6 feet are not guaranteed to be normal in all other functions.
The trick is to find a balance between being normal enough in some behaviors to fool other people, yet still retain the part of you that makes you, you. Maybe that's easier said than done. Believe me, I have the same struggles.
Did Courtney Love kill Kurt Kobain?
Probably. If not directly, she contributed to it by being crazy, and by fueling his drug use. Kobain used heroin for therapeutic pain relief, I believe for stomach ulcers. Nevertheless it was illegal, and she contributed to his death simply by taking part in using heroin without a doctor's guidance.