Motivating a Struggling Student

hi there. I need your advices and help. my sister is a a collage student and 6 month ago broke up with her boyfriend. She was a great student and was participating in a lot of collage activities. She is not the same person any more. She is not interested in anything. The thing that it's complicating the things is that her ex boyfriend was her college and they were doing all together ... She just don't want to do anything anymore. please give me advice how to motivate her to continue her studies.