Forgiven. (A Harry Potter fan-fic.)

Issadora went to Azkaban innocent. Fifteen years later when she was released because of her innocents she's not sure if she is still loyal to the dark lord she is confused and angry.
Sirius Black escaped from Azkaban, he promised he wouldn't leave Issadora but he did he seeks her forgiveness and understanding, Severus Snape doesn't know how he feels about Issadora leaving Azkaban but some old feeling he thought he had burned the day she was locked up are stiring.
Can Sirius and Severus put aside their differences to help the confused girl? Or will their rivalry push the girl away from both of them?