The Evolution of Us by D. Kelly

They say most people meet the person they will marry while in high school. Balancing one another perfectly, Holly Ryan and Declan James were together through most of college—until their relationship blew up, leaving Declan with more questions than answers.

For the past two years, Declan has tried everything he can think of to earn Holly’s forgiveness, but even if he manages to help her let go of the past and give them another chance at happiness, she still has a secret. Not to mention, she can’t get over the revolving door of women he seems to have coming in and out of his apartment. Declan is desperate to prove to Holly she’s the one for him and isn’t above using his celebrity status or enlisting the help of their friends to win her back.
All’s fair in love and war, right?