Unleashed - Cherrie Lynn This is another that's closer to 4.5 than 4.

One of my favorite genres in erotic romance is friends to lovers and this was one such story, and wow they waited a long time. Kelsey carried a torch for Evan for ten years. It dimmed a bit during her marriage, but he was always special to her. Evan, on his part, recognized her marriageability in college, but was scared to death of hurting her -- he knew he wasn't commitment material at the time. He introduced her to his best friend, and Kelsey ultimately married Todd. Unfortunately (or fortunately), Kelsey finds Todd in bed with Evan's fiancee, so both relationships break up. But Evan still has his honeymoon trip to Hawaii that would have gone to waste, so he invites Kelsey along. And wow... what a great call. :-)

They were so good together. The sex was super hot. Evan was quite patient with her, knowing she was still holding back a bit, but understanding how badly she'd been hurt. He had been hurt, but it was more of a relief for him that his engagement was ruined. When we got his perspective of how he felt for her, my heart melted. And when they returned to reality and things went to hell in a handbasket, my heart broke so many times for them. I was so proud of Kelsey and how she turned that around!

I read Rock Me first, not realizing this one was the "first" -- it's not really a series, I guess. I liked Rock Me, but I really liked this one.