For many writers without platforms or a field of expertise, collaborations can help keep those book contracts and, if they’re lucky, royalties coming in. Unlike with ghostwriting, having an and or with before one’s name on a book jacket is also a way to get credit for doing the heavy word lifting, even if the coauthor gets the glory. And while many writing collaborations can be like happy marriages, some end up in holy acrimony.

Although nearly all my book collaborations have garnered heartfelt acknowledgments, I’ve had a few less-than-perfect unions. One particularly egregious partnership was with a coauthor, “Cindy,” who, during a celebratory lunch with our publisher and literary agent, asked the agent if she could borrow money against her advance to fix her mother’s furnace. I later discovered, as we began working together on her relationship book, that she was functionally illiterate. Even with spell check, she could not string a proper sentence together. Nevertheless, I persevered, turning a booklet of bromides she had stapled together into a bestselling book that still earns royalties after 20 years.

Then, when the time came to promote the book, I learned to my horror that Cindy hadn’t bothered to read it. She’d done a lot of TV appearances in the past to promote her business and was arrogant enough to think she could wing it. But when asked about a tip from the book during a segment on a major network, Cindy stared blankly at the show’s host, like a deer in klieg lights. The interviewer kindly prompted her with the answer so she could regain her footing. After this incident, I demanded that she read the book three times and commit its contents to memory, so neither one of us would be humiliated in the future.

Having finally read the book, Cindy continued the publicity tour, using the publisher’s credit card to send me a bouquet of flowers (how thoughtful) and charge other personal items, including numerous lattes from Starbucks, long after the tour had ended. The editor sent our agent the bill requesting that Cindy reimburse the publisher. Fortunately, she did.

With book sales climbing, our publisher offered us another book deal that Cindy turned down, saying her “Hollywood people” told her the advance was insultingly low (it was substantial) and that she was the next Kelly Ripa, destined to become a TV star. The media attention had gone to her inflated head. The TV offers never came, but she was outraged that books were being published with similar titles. After I explained that a book title can’t be copyrighted, she hired a lawyer to send cease and desist letters to the book title thieves, who included a celebrity comedian whose book sold in the millions. “Why is he allowed to profit off of our ideas?” Cindy whined in a flood of emails. “We were first!”

In yet another incomprehensible missive sent years after publication, Cindy bitterly complained that we weren’t doing enough “to promote the brand.” (For several years I wrote a monthly relationship advice column for Showtime’s myredshoediaries.com with the book title under my byline.) I reminded her that she had turned down the book deal that would have kept her name and momentum going. I offered, yet again, to cowrite write a sequel, which she refused.

Cindy finally decided to sever our relationship (much to everyone’s relief), so we can only hope that every angry inch of her has disappeared into the ether of has-beens.

I’ve spoken to many colleagues about their own unpleasant scenarios, and every coauthor who has been in the business long enough has a story to tell. And while collaborations like these can make writers wary of hitching their wagons to anyone who might flake out or freak out, I’ve learned to pay attention to those red flags and to listen to my gut, and perhaps you should too. Money is nice, sure, but so is your sanity. If someone shows early signs of being high-maintenance, walk away.

Jodie Gould is the author or coauthor of 13 books, including 'Beautiful Brain, Beautiful You', with neurologist Marie Pasinki.