boyfriend's best friend hates me....

i'm 21 and have been in a long distance relationship with my partner for over two years. he lives in the uk and i'm based in north america for school, so we don't get to see each other as often as we'd like. but we're committed and have plans to move in together and marry eventually.

we do have our problems, largely because he is autistic (asperger's) and i have a variety of mental illnesses stemming from childhood abuse and sexual assault. we can have huge arguments over petty things, but we always forgive each other and move on without holding grudges. also im an extremely private person with very few friends- academics are a bigger priority for me than friends, and i work full-time in my field. my boyfriend is the opposite (which is partly why we're a good match). he has no interest in higher education and loads of friends. they party pretty rough, although he rarely joins them, and through twitter and fb we've sort of gotten to know each other.

my boyfriend's best friend is another girl. she was the one who encouraged him to tell me he liked me two years ago, but since then she's also been privy to our disagreements (which, admittedly, i do allow to spill out into public forums like twitter) she has taken a very marked dislike to me. i have attempted several times to patch things up with her, but without her having any knowledge of my mental illnesses its almost impossible for her to understand why my boyfriend stays with me when i seem like an awful person.

things came to a head last night when she blocked me on all her social media and told my boyfriend that i was abusive and he needed to break up with me. she did not say anything to me about this: i noticed she was missing off fb and spoke to him about it, he addressed with her, and she told him to break up with me.

i am at a loss as to what to do bc i do not want to be the girlfriend who cannot get along with my boyfriend's friends. i have no real problem with this girl, and although my bf vents to her when he's frustrated with me, he talks about me in positive light more than that, but she chooses to focus only on the negative aspects. as far as im concerned she has absolutely no business making assumptions about me without bothering to get to know me first. i have tried to make friends with her, and she has refused.

im supposed to go see my boyfriend this fall, but with things this crap with her im seriously anxious about going- she's extremely confrontational and i've very nervous. i have no idea what to do. any advice would be much appreciated.