Ela, I think it is maybe safe to assume that whether your diagnosis is right or not, that you understand who your mother is as a person and can represent her behaviours pretty accurately. As such, the description is somewhat familiar as Asperger's Syndrome, which is hard to diagnose in women to begin with, and even harder if the person has been masking (basically, pretending to be like everyone else by hiding their symptoms as much as possible) for many years.
But whether you are right or not, your phrasing is very unfortunate, and I think you may need to step back and rethink your approach.
Asperger's is part of the broader autism spectrum, and as such it relates to the way the person's brain is wired, which in turn impacts on every aspect of the way that person sees, understands and interacts with the world around them. If she is on the spectrum, she is not, for example, rude or indifferent at all, she is being literal and direct. It is how most of us are. You can't fix that because it isn't a fault, it's a fact of an Aspie's life.
The characteristics you describe are therefore not faults, they are how she is wired, and while they may be difficult to understand and rather problematic to handle at times, the only thing you can do is cherish her for the strength of values she has, and learn how not to be embarrassed when she says or does something you don't agree with or that is a bit abrupt or awkward.
Take the issue of her dislike of being the target of an injustice for example. Imagine that she has spent her life being blamed for things she didn't do, or didn't do on purpose, of being the butt of others' scorn. Would that frustration at injustice not make sense? Would you not rush to her defence because of it?
She doesn't edit the things that come out of her mouth because she can't. Most of us are like that and even when someone tells us we may have said something inappropriate, we can't see why it would be. Facts are facts and that's what we deal with. And black and white, yes, that is not untypical for an Aspie, but again, not something you could change however hard you tried.
The first step for you in resolving this is perhaps the hardest, acceptance. Accept that your mum is exactly who she is and respect her for being exactly that. She is not defective, she is remarkable. If she is on the autism spectrum, she has already had a hard life and this is something she will have always because it can't be cured and will never go away. After you learn to accept her as she is, and find that you can respect her, then find ways to support her. Talk to her. Instead of thinking of the embarrassing things she says, focus on the great things she does, and if you find she is indifferent to things in your life, find a new way to approach her. Look for the things she is interested in - Aspies tend to focus on 'special interests' and engage with her on those things. Once inside a special interest, you will find it much easier to connect with her.
And in the meantime, read as much here as you can find on autistic people describing their lives. You may find that your mother is a very remarkable person, experiencing what she does, yet seeming to be almost as normal as you!
