I'm searching for a book title

I once read a book about a girl who is very into astrology and believes in it because it's the only thing her dead mother has left her. She meets two boys who are brothers, both fall in love with her and she feels more drawn to boy 1 but her horoscope says she should stick to boy 2. In the end she chose boy 1 because boy 2 lied about his zodiac sign. What's the name of the book or the author? I totally forgot but I wanna know for a friend. I think the word 'stars' was in the title.