Look, I'm WAY too tired to even concieve a rational argument, right now (Gears of War 2 CONSUMED my sleep), so if I came across as a little too angry, it's probably because I have all of 5 books from Marvel that I actively enjoy reading, and Amazing Spider-Girl is one of them (DD, Cap, USM, Wolverine [until Millar leaves], and ASMF being the others). Watching the only monthly that features my favorite character making progress in his life get cancelled as it getting REALLY DEEP into a GREAT story arc just annoys me to no end.
As for Marvel not pimping it, I can't recall a time when they DID promote it. I remember reading about the book in Wizard, and seeing the book on shelves, and that's all I ever heard of it until I started coming to the Hype. I'd never seen an ad, an event, anything involving Spider-Girl. She was just....there. MC2 came up around her, and the entire line was cancelled (thankfully, as the supporting characters were pretty lame), and that left MayDay in her own universe.
May's had the deck stacked against her since the beginning, and I guess it's a blessing that she made it this long.
I will say that, despite how paranoid it sounds, Doc_Ock_4Mugen's explanation
feels about right. I hat eto sound all "conspiracy theory" and everything, but the numbers haven't changed THAT much since BND, and for them to cancel it as they get further and further away from the "good ol' days" of a married Spidey, well, it just seems to convenient to be coincidence.
Still, with all that, if more people would simply buy the book, this problem would take care of itself.