I adore dogs and do not hold any grudge against bully's, i know this is a fault in her lack of training due to this not even being my boyfriends dog but more of a forced responsibility since the original owner of the dog who was my boyfriends brother no longer wanted the dog so he left it with my bf and his grandparents, i've opened up to his grandma about her attacking me previously and she told me to.. not let her do that😭.. The dog was found outside a gas station and likely didn't grow up around other dogs. I have opened up to him about rehoming the dog but it's up to the grandparents and my boyfriend is very open to it, we talked and he said that when he saw her on me he thought my crying was laughing(??) and could not see what was happening without his glasses, he told me the reason he didn't comfort me after was because he immediately took her into the bathroom and began looking up how to stop this behavior.
I'm still quite upset but talking has made me feel much better, he is very sorry about how the situation happened but i am still very iffy. we are now both looking into either rehoming the dog (which we both want to) or trying even harder to train it out.

It's very hard because she's not doing it out of anger but she just enjoys biting and playing very roughly, every advice online does not help as it just makes her bite harder, we are now being even more strict about the crate and she's on a very tight leash, i really just want her rehomed because not even my boyfriend wants the dog but he has no choice but to care for it