Help me with my friendship problem?

so im in middle school, eighth grade. me and my bestfriend have been friends since 4th grade. and today i sat with her in the bus and she ignored all the way home and kept talking to her firends, she didnt even ask me was i okay. when we got off the bus i just walked away calmly and went to my sister. at the night she didnt even call to see if we were okay. she has a boyfriend theyve been dating for 2-3 months. she says she really loves him. and hes the reason why were growing apart. shes like hypnotized. we had a fight once about him but i was the bigger person and said hes important to her so i understand, but now its like it all about him its only about him, and trust me im not the only person who thinks that. i told her that this is middle school, and that she has the rest of highschool and college to date. she always frind another guy but a good bestfriend is hard to find. friends last longer than boyfriends. shes been defending him all the time. the reason i find it hard to believe she likes him is because in 7th grade she liked this guy and they went out she also said she loved him and that she couldnt choose between me and him and i thought we were so close that i be'd first. and now she completly hates him. i told her that guys are just a cycle. and now i think its happening again, shes letting a guy get in the way of our friendship. and in the hallway just recently she gave me the ***** stare, like she was mad at me. and she was only mad at me cause she thought i was mad at her? i wasnt mad at her im not speakin to her right now though, i rather not speak to her at all, if shes near johnny. i dontwant to get angr all the time so im lettting them have there space thats what she wants i guess. and in the end of the da she usally waits for me to go to the bus, but now she usally forgets about me and leaves with her bf and she told me she didnt wait cause she didnt know where i was well my locker isnt that far from her i told her im always at my locker at the end of the day ofcourse. so now she still hasnt messaged me called me or anything, she means the world to me. she doesnt relize the things she can do to me. she even has the ability to kill me. in the past not long ago, she hurt me so much i couldnt take it anymore it only took my a second to want to die. and actually grabbed a knife and stabb myslef but i thought twice and said dying isnt going to solve anything. why wont she understand that friendship means more then middleschool relationship? we been through this many times, and when she knows im mad at her she still laugh with her friends like crazy evevn though she knows im sad. is it that easy with out me? were you really ever my friend? and she was looking for me once but then i didnt answer so she just ealked away with her bf and couldnt even leave him for atleast a minute to talk to me? i need your opinion am i overreacting or is she to mnea?its like everytime we get angry she gets meaner, i told her waht she could do to me and all she did was look down and said nothing. she doesnt care. i really dont knw what to say. how could she do this. is it better to let go and be happy?