Charlie will be missed by me.

But let me say something. His character evolved to the point where it couldn't evolve further. There was nowhere left to go. He went from being a drug addict to a hero. He had to die because there was nothing else that could be done. He was redeemed to the highest point.

I also found it interesting that Jack and him switched roles. In this episode Jack became the druggie/alcoholic and Charlie became the hero. Both actors were amazing. But yeah, I just found that interesting. I don't know if it's already been brought up. I looked and I don't think it has.

The hero devolves into a junkie.
The junkie evolves into the hero.

Yeah, kinda.

There was so much going on that I didn't even realize that they had swapped roles with each other.