Meaning: The girl remembered the doll for the rest of her life.
Choice of Words: "Memories" are recollections of past experiences or events. "Doll" refers to the toy figure. "Lasted" means to continue for a long period of time. "Lifetime" is the entire duration of a person's life. Putting these together, "Memories with doll lasted a lifetime" indicates the girl's experiences and思い出s with the doll remained with her throughout her life, leaving a lasting impact.