...It's autobiographical, about a gay guy in his mid-20's (?) living
in NYC, with bipolar disorder, getting caught up in, lost, and
eventually surviving the New York underground subculture. Talks about
his dealings with drugs and handlings of  destructive
habits/addictions all the while being mentally ill.  For some reason I
thought the title was "Astroboy" or "Astro Boy" but I haven't had any
luck with finding it.

You were close with "Astroboy." I'm sure you're thinking of
"Electroboy: A Memoir of Mania," by Andy Behrman.

"Put sex, drugs, art forgeries, and manic depression into a blender,
run it at top speed for 10 minutes, and out pops Electroboy, Andy
Behrman's high-octane autobiography. The story begins as an
exhilarating view into the manic's world, with spontaneous flights to
Tokyo, sketchy East Village bars, and a nonstop inner dialogue that
makes your pulse race just to keep up...

Between titillating tales of stripping for extra cash and excessive
drug use, Behrman charts his experiences with therapists and a wide
variety of prescription medications. No clear picture is presented of
his attempts at counseling; there is much skipping around between
therapists, from whom he manages to hide the extent of his
difficulties... Like many confessional memoirs, Electroboy is a blunt
tale that relies heavily on the shock value of his über-yuppie
behavior..."

Amazon: Electroboy 
http://www.amazon.com/gp/product/0812967089

I hope this is the right book. If not, please request clarification;
I'll be glad to offer further assistance before you rate my answer.

Best regards,
pinkfreud