It is also a tribute to hard lives that still have their great moments. Just because people have a hard life doesn't mean that their lives are not worth something to someone.
This excerpt talks about the last time Mike DeStafano saw his gal.
You can read the whole story here:
And then I pass the front door, and all these nurses are standing out front, and they’re all crying. They’re watching us, and they’re crying. And I didn’t know why they were crying. I was like, Why are they crying? I didn’t get what they were seeing. I didn’t know. Because I was just in it; I was living it. I knew my wife who had suffered, she was a prostitute, she was a freakin’ heroin addict, she was beaten by pimps — this was her past — and then she ends up with AIDS, and she’s dying, and all she wants is a goddamn ride on my motorcycle.