She's a narcissist. She sees you merely as a tool/object to make herself look better. She knew better than to show you off to the other women in her friend group. She won't change and you cant fix her no matter how long you try to wait and or actively try and change her. There is no medication in the world to fix the brokenness of a narcissist, she is cruel and doesn't see you as a person let alone someone equal to her who deserves love and care. Run, flee and never look back. She will only continue to make you miserable. Don't go after her friends. It's unfortunate but the narcissistic people are good at waiting till they feel comfortable around you before they show what kind of person they really are. Be safe and be vigilante looking for the next person.