I don't think you should ever try to make things up. We all lead such strange lives that there is no need to. Use your own experiences and then twist it a bit.
Clearly, Ms. Bainbridge is an honors graduate of the Write What You Know School. But I maintain it can be much more exciting for a writer to plunge into situations and emotions she hasn't experienced and doesn't understand. Sure, wisdom and experience are required to make a novel ring true. But what's wrong with aquiring that wisdom and experience during the writing process? Research is always required to craft a good novel; more than a little revising and refining is always necessary, as well. So the "ignorant" author is always afforded plenty of opportunities to get her story straight.
I don't ask for the author's credentials when I pick up a novel. I don't care who she is, where she's been, or what she knows. All I ask is that she make me believe for a few hours that the characters in her story are real people in real situations. Whether she can do that has little to do with her real-life experiences; it's her writing ability that counts.