Pennyroyal Tea

I'm on my time with everyone I have very bad posture

(this first part is about the rise to celebrity mega-stardom. He is saying I have no time to myself anymore, my public identity is now fused with that which is projected. I'm not strong enough to endure it).

Sit and drink Pennyroyal Tea Distill the life that's inside of me Sit and drink Pennyroyal Tea I'm anemic royalty

(Everyone knows Pennyroyal Tea was given in old times to induce abortions. He is saying I've drunk the kool-aid poison willingly, and as a result my life's been changed, like the conversion process of alcohol, and a result he's sick royalty. Anemia means literally "lack of blood" or life force/energy/will. Kurt has sacrificed his true self for projected royalty).

Give me a Leonard Cohen afterworld So I can sigh eternally I'm so tired I can't sleep I'm a liar and a thief

(Leonard is all about vulnerability, loss, helplessness, hope and God. When you combine those together you get what Dylan indicates in Knockin' on Heaven's door: I'm done, my illusions are finished, lay my guns in the ground, I'm too tired to keep fighting this war. This is what's meant by being too tired to sleep. It is an illusion to the Beatles song "I'm so tired." It reveals a weariness unfathomable. And at the same time Kurt feels fake, inauthentic. He knows his talent at writing songs does not surpass the phoniness he feels from stealing from others works, such as the pixies etc. But he is way too hard on himself. What he created was unique, and expressive of genius)

I'm on warm milk and laxatives Cherry-flavored antacids

(unfortunately, this must be a reference to heroin, like Trent Reznor's hurt and Leonard Cohen's "The Butcher," as well as a number of Beatles and Velvet Underground songs. Heroin, for many tortured, but successful, artists, is the drug of choice. It obliterates everything. Perhaps in the end, Kurt realized he's only turn out like Layne Stayley. He knew this, so he opted for self termination before the ultimate in pathetic abandon realized itself).