My girlfriend says that I am not in her future?

My girlfriend and I have been dating for 10 months. We love each other very much and have a lot in common. Just recently we had a talk about our future. She said that her dream is to go into theatre full time and that she will not have enough time for a relationship. She also said she never wants to get married. And I quote "I'm going to give all of my love to theatre." It was a heartbreaking quote. I told her that was she said was very hurtful, and I cried. All she says now is "who knows, I could change my mind." Even though she may change her mind, it bothers me that I am not included in her life dream. What should I do? Should I break up with her? I want to get married eventually. Any advice??