I think the ending was a bit of a cheat. Having her husband die sanctified Irina's marriage and allowed her to construct her choice to marry and stay with Ramsey as the right choice; as the only choice that would lead to happiness. Exploring an ending that allowed Ramsey to live and explored whether Irina's love, lust, sexual obsession or whatever it was she had for Ramsey could withstand the pressures of poverty and insecurity would have allowed for a more complex exploration of the struggle to find a balance of happiness, peace and passion without a woman's life.
The also author seems to be trying to make a statement about the importance of love and emotional commitment as the most basic need for a woman. However, she doesn't really explore whether this need is basic for men. In addition, I finished the book still asking myself who is Irina outside of her relationship with a man? Both of Irina’s husbands exist without her (and seemingly pretty happily), but Irina almost fades away without the protective arms of a man. Her need to be romantically and sexually connected to another is all there really is of her. I find this to be a tremendously sad way of viewing women and relationships. Shriver seems to be saying that not only can women not have it all, but they really don't even want it all. She eliminates complexity and layers from women in a way that social conservatives would approve. Her literary trick implies that Irina only had two possible paths, stay with a man who leaves you tepid but safe or stay with a man who ignites you but makes you miserable. In the end, I found this to be a very dichotomous exploration of oft-played scripts for women which foretell of only two choices in life.