Addicted to YA discussion

I can't remember the name of this book for anything so any help would be appreciated. It's about a girl whose parents died and she is raised by her dads best friend. She ends up going to a new school and she learns she is a werewolf. She has two rain drop birthmark that match her mate. And she ends up slapping her mate because he was flirting with a girl and that's how he found out she was his mate. They are both very wealthy. There is also man who is after her who was also after her mother.