I'm assuming that your life has followed pretty close to the television show based on world trends, but you'll have to forgive any incorrect assumptions.
Dr. Deaton figured out very early on after Peter attacked me what I was, and after I predicated a horrible crash he took me in and started giving me proper training. Because I was under Deaton as a banshee/emissary in training, I served as a sort of intermediate between the Hale and McCall pack, but honestly more towards the McCall pack since that's where Stiles and Allison were. I was able to prevent Erica and Boyd from dying and Scott, Stiles, and Allison from having to sacrifice themselves in order to find their parents.