Engaging the Enemy by Reese Ryan
Parker and Kayleigh were childhood friends until Parker's betrayal involving her father caused their friendship to turn to bitterness and disdain on Kayleigh's part. Many years have passed since that time and now Kayleigh has something that Parker needs for his family. When Kayleigh finds out that she needs a favor in return, they strike up a bargain where Parker agrees to be Kayleigh's pretend fiancé in exchange for what Parker wants. To reacquaint themselves with each other, they decide to go on 10 dates in 10 weeks. The more time they spend together, the more emotion starts to enter their relationship. Despite stubbornness on both of their parts, they find a way to love each other despite the past. There's even a secret or two that are totally unexpected. Ms. Ryan has written an excellent enemies to lovers story that doesn't disappoint.