Yes, in the pre-Me Too times, this sort of thing generally happened (ie., women were not believed). It still happens.
This book is sort of a hyper-realized version of the Same Old Story (fiancé is a giant jerk who thinks he knows everything. he's dismissive of you and treats you like crap. so you drag your self respect out of the dustbin and leave. but for Romance Reasons, he can't stop thinking about you so he tracks you down, slimes his way back into your life cuz you're tired, and smooches his way back into your good graces. But with lots more $$$ and a private island.).
I felt there was enough groveling in this book to call it OK. But I can't believe she ended the book before the baby was born. WHY WOULD YOU DO THAT WHEN THE BABY IS LIKE THE ENTIRE POINT OF THE BOOK.