Greek Mythology: the story of artémis and Callisto

So originally Callisto was a nymph daughter of Lycaon the king of arcadia and one of Artemis hunters and like Artemis and all the other hunters she has to take a vow of chastity and that means that she swore to remain unwed ( quick information in ancient Greece sex was only seen as valid when there was at least one man involved.) which means that Artemis and her hunters could have sex with each other and not break their vows.

callisto and artemis started spanding more time together and slowly they fall in love with each other very deeply but unfotunetly she was loved by zeus .zeus knows that callisto took a vow of chastity so he know that he cant show up to her and seduce her like every other woman so he basicaly stolked her and observed her and he sees her relationship with his daughter artemis and he decided that thats hes way in so desguided himself as artemis and shows up to calliso and obviously she didnt doubt it its just her lover artemis so they sleept together and then she ended up bieng pregnant and she doesnt know how because as far as she knows shes never been with a man so she hides it until shes about ready to give birth and one day while shes bathing artemis comes in and sees callisto with her nine month belly and furious cause she thought callisto sheated on her with a man and broke her vow that she dedicated to her. so banishes callisto from the hunters and shes heartbroken and extremly angry and upset so weus sees that he turns callisto into a bear out of protection and her are two versions the end of the story the first one which is that artemis kills her by accident when she was huting and the other one is that callisto gives birth to her son arcas who becomes kind of arcadia and one day hes grown and out hunting and she sees him and forgot that shes a bear and goes to him and he kills her and for her memory to live she got pust into the stars as the constellation ursa major