Honestly, when you start talking about genres, you're talking as much about the business side of writing as anything else. Certainly there are elements of reader expectation that play into various genres, and those are important, but it also becomes about packaging, placement, audience....In the end, I'm not a fan of labels. I think the best fiction blurs the boundaries between genres, stretches and breaks them.
Hands down, the hardest part for me is coming up with an idea. I spend about 14 months writing a book, and that's a lot of hours spent thinking about a single project. I simply have to love the idea. I'll go through dozens of workable ideas until I find the one that lights my fire.
I can be a little OCD when it comes to my writing.
Whenever I write about motherhood - and I write about it a lot - I am drawing on my experiences as a mother and also my experiences as a daughter.