Creating a better family dynamics with 21 year old daughter - and going forward

First time I've posted here and not sure where to start, 

I think my 21 year old daughter has autism/ADHD? To the outside world she is confident, articulate, pretty, intelligent. She is inherently kind, truthful and has a determined personality. She is doing well at uni and holds down a regular holiday job to earn some money.

But at home her anxieties spill out into anger and rage at family members. She has severe  misphonia and other sensitivities- especially around food. In some ways she is highly organised - eg she is very reliable at work/ uni yet in others she is very disorganised - bedroom, finances etc. She talks of masking and is exhausted very quickly and needs lots of sleep and headspace. My presence seems to trigger constant irritation - the way I talk, how I eat, the clothes I wear. So I go into avoidance, a sort of neutral to keep the peace. We rarely share the same space - except when I drive her to work. This anger is directed at all close family members and it's hard not to take it personally at times. I wonder if she has demand avoidance too, because in the past, asking her to do things triggers rage. So I don't ask for help with house chores when she's at home because it is the 'easy' option. We don't talk and she has said in the past that she has no trust in me - I know this can be pretty normal for parent/adolescent relationships. I have good relationship with her other siblings and would love a better relationship with her if I could. 

She was  a quiet thoughtful child, but at aged about 10, another sibling was very unwell for many years and it was a highly stressful time  and I blame myself for letting her needs go under the radar as she went through adolescence. She is angry about this too - quite rightly - but at the time I thought it was her reaction to the family illness. She developed an eating disorder too and does not have a good relationship with food. I regret not having my eyes open to her needs then, but I can't change the past, I can only do what I can now.  I know there have been friendship issues during teenage years and wonder if there are similarities here with Ellie Middleton in her book 'Unmasked' where there is 'pretty privilege'. I have tried to have discussions about seeking professional counselling - and I think she feels that I see her as a failure or 'broken' for asking this - I don't at all - but I think it would help her understand herself to navigate challenges in the neurotypical world and also help us as a family to know what we can do to give her space, but also feel that we are not 'walking on eggshells' all the time. I'm very proud of all she has done and who she is, but when I tell her she says she does not believe me. Like other parents on this forum - I have felt the crappest parent at times - I have unwittingly made so many mistakes - have not understood etc etc - but I do want to try to understand and help us as a family. 

I'm not sure how to start these conversations with her - I have tried, probably very clumsily. But it seems the only way forward. Any advice gratefully received.