best friends gf

my homies gf was playing with my hair n shi during class and it was lowk giving me tingles and almost put me to sleep. really sucks though because: 1. shes dating my best friend 2. she constantly references me to her little brother (comparing looks, behaviors, says i remind her of him) 3. i already confessed to her at the beginning of the school year and she said we should stay friends and then texted my bro two days later saying shes liked him for like 3 years now, guess me confessing gave her the confidence to do that. its alr tho because my homie came to me when she texted him and asked me if I would be ok if they started dating cause he knew I liked her and knew she had rejected me. What I dont get is why she continues to treat me like someone closer than a friend (hits me without hesitation in a semi playful semi angry way. constantly asking if im ok when I look depressed around her and my friend, playing with my hair, etc) even though she stated she just wanted to stay friends, but when us three are hanging out me and her boyfriend get almost the same treatment minus some minor relationship activities, but she attacks him in that playful way she does to me. i dont get it. being around then every day getting treated like that but knowing im not and cant be in a relationship with her takes such a massive emotional toll on me that i get more and more ready to end it every day. i dont know what to do anymore. plus another friend of mine is also in a relationship with a girl I liked but i never had any courage to say anything to this girl but it still takes the same toll on me. its whatever though, ill just grit my teeth and bare it.