If a girl dreams that she is a bridesmaid, then it means she will get married very soon. If her dress is torn apart, then she will meet someone very mysterious.
Dream dictionary: Bridesmaid dream meanings
If you dream that you are one of the bridesmaid, it shows that you are very supportive person when it comes to other peoples accomplishments. The dream also shows that you wish the best for the people who are getting married and in your waking life you will be one of the bridesmaids.