HELP!

Hi All, I hope you are all staying safe and sane in these strange times.

I am a mother of three teenagers, 19,17,16, girl, girl, boy.

My eldest displays many of the symptoms of high functioning autism. She was diagnosed with Irlens syndrome and dyslexia in year 8. When she was tested again to confirm the need for extra time for GCSEs in year 10, the tester mentioned autism. When she told me, I asked if she wanted to investigate further but she declined not wanting to be labelled or restricted in any way. She forbids me to talk about it to her or her siblings. I have discussed with her father but she would not want to talk to him about it.

I think she has showed signs for years looking back but the teachers seemed to poo poo my concerns and blamed it on other things. She was very tearful as a small child especially when doing homework or something that challenged her. She is a compulsive liar, lying about things she is very obviously going to get caught out on. She is very violent and has the shortest tolerance I have ever known. The main focus of this violence is my other daughter as there seems to be a fierce competitiveness towards her and maybe some jealousy. 

This is now having a massive impact on our family life with the other two children asking when she is leaving home, me not booking days out, meals out or holidays. Her behaviour has recently ruined the trip of a lifetime to Japan. She seems to lack insight into her behaviour often blaming everyone else and focusing on something that wasn't actually said or done.

I guess what I am asking is: how can I get a diagnosis when she doesn't want to discuss it? Are there any negatives about being diagnosed ie restrictions in travel, jobs etc. Does anyone else have a young adult who has these violent outbursts? If so how do you manage them? How can I get the family on board if she won't let me discuss it?

She punched my other other daughter in the face last night during a perfectly reasonable conversation that tested her resolve. My husband ( her dad) lost the plot with her and she has left and gone to stay with my sister (whom she claims to hate but has secretly visited numerous times over the last six months!). I am at my wits end and of course, as the mother it all stops with me.

Thank you for reading this, I am grateful for any help or suggestions.