The Break Up Queen by Mai Moonshine

Audrey Monroe, best-selling author of The Bad Boyfriend Detox series, is known as the “Break-Up Queen” to her adoring fans.
But her critics say she cares less about helping women heal and move on from bad relationships, and more about dragging them down into a man hating pit of bitterness and eternal singledom right along with her.
Readers want Audrey’s assurance that a happy ending is still waiting for them once she’s helped them to move on, but she refuses to sell them on something she doesn’t believe in for herself.
Her publishers give her an ultimatum: prove them all wrong and bring a convincing boyfriend to the release party of her next book, or it’s game over.
Audrey doesn’t know what to do until a chance encounter with ex-boyfriend Dean Palmer gives her an idea. She’ll help save his failing bookstore and in exchange, he’ll pretend to be her loving boyfriend.
However, Dean is much more than just an ex-boyfriend. He’s the ex of all exes. The one who broke her heart, inspired her books, and launched her career. The heartbreak he caused is the very thing that has left her so bitter, with her whole career at stake.
Now, as old memories and emotions begin to resurface, Audrey begins to wonder if she’s made a horrible mistake…But was the mistake in thinking she could trust Dean not to screw things up after all this time? Or was it breaking up with him in the first place?