What does the title Me Before You mean?

Jojo Moyes's novel Me Before You is a story about Louisa Clark, a young woman who becomes the caretaker of a paraplegic man named Will Traynor. The title could have a couple of meanings, but on the most basic level, it is about Louisa's life before meeting and caring for Will and how her relationship with him changes her forever.
Louisa has no experience as a caretaker, but she has recently lost her job in a local cafe, so she applies for the position. It is quite demanding, and at first, her patient Will is very difficult to get along with. Over time, though, the characters challenge each other, and they both grow. Will is able to experience joy again, despite his physical limitations. Louisa learns to expand her horizons and begins to travel more. After Will's death, Louisa is left with a good deal of money from his inheritance, which he hopes she will use to travel the world. Indeed, she ends the novel in Paris reflecting on their time together.
Louisa's character changes as a result of her time with Will, and she believes it is for the better. Her world opens up in a positive way and she becomes more adventurous and carefree (somewhat ironic considering the tragedy of losing Will). Moyes wrote another novel called Me After You, which follows Louisa after Will's death. All of these details suggest that the title refers to Louisa's life before Will and how she evolves over the course of the relationship.