Does my friend not care about me?

OK like i feel like my friend hates me. she always ditches me for her boyfriend and she knows i don't like him BC hes rude but then she just hangs with him all the time and whenever i invite her to my house to sleep over she ended up leaving bc she said she wanted to go home but then she went to her cousins house and she left my sisters arty to go hang out with her cousin at the park and every time there's something wrong with me all she says is aww and shes such a slu she texts other boys behind her boyfriends back and i always do what she wants and i actually care if she crys and stuff and give hr advice what should i do?