Hi. I am sorry to hear of this within her. It seems like her anger is covering up for some deep feelings of sadness, fear or many other emotions that she may not be able to express. She may need an outlet to work through some of these issues...whether it be with clergy in your church or a therapist to help her uncover what is going on and why she lashes out and keeps friendships at bay. I hear that you are working hard to help her and hoping that smoothing things over will work, and it may, temporarily, but it sounds like she needs some more in depth processing of why she is feeling the way she does.
Her putting the blame toward others is another reason why I suggest her getting some outside support. In a quiet moment, when things feel calm, I would let her know how you love and care for her and you can see how upset she gets when others are rude and she feels angry and you can feel that anger too. Let her know you desire that she has a happier life, one that is free from anger and resentment and sometimes talking with someone short term could help to ease those feelings. In the end, it is up to her to go or not and if she refuses then you are left with continuing to deal with things as they are. That is a tough spot for you. But go to her with love, care and empathy and hopefully she can hear you and desire for things to be different for herself and her connection with you.
Please let me know how else I can support you further. If all good for now, please take a moment to click on the rating tab to offer a rating of my support. Thanks so much in advance.