My stories aren't about problems. I prefer the term challenges. Even then, my books are not about challenges. They're about characters who have challenges. There's a subtle difference.
In Pen and Ink, Pen Swan has multiple challenges, most of which have to do with facing reality as it is rather than as she believed it was. As a happily married wife, Pen assumed she'd have children. Her husband wasn't really against the idea, but he wasn't too enthusiastic either. Finally, tipping into the second half of her thirties, Pen bit the bullet and suggested it was time now. Five years later, she was not only still childless, but widowed too. A well-meaning friend suggested she should "put herself out there", as it were, and Pen had a new challenge; to make up her mind whether to accept middle age or flip the metaphorical die and have another go at wife-and-motherhood. A divorced friend of her late husband fancied himself in the role of Pen's husband number two. Challenge? Accept a pleasant old friend just for that one last chance, or hold out for a future in which her window of opportunity was closing by the day. Pen decided to sidestep the whole thing and get herself a cat.
She ended up with a cat and a husband and twins and a whole new set of challenges.