Laura

"They're as common as weeds, but - you - well, you're - Blue Roses!" - The Glass Menagerie, pg. 1283

I think Laura was changed because of her experience with a person from the real world. Jim had insight about life and he was good at making Laura feel comfortable, which rarely happened. He told her she was beautiful, which had probably never happened. Laura was devastated when Tom broke one of her glass menagerie animals, but she didn't mind when Jim broke her most precious one - the unicorn. I think that was the moment Laura stopped living in her own little world. She knew that things wouldn't always be perfect, and she would get on without Jim or her unicorn. Her response was almost numb. I think years of succumbing to her mother's constant remarks and orders, she began to live her own life. Jim was the most realistic character, as stated in the descriptions, and he was exactly what Laura needed.