hurting

I'm feeling really hurt, confused angry. I don't know what to do. My eldest child, 22, is picking fights with me, she has depresion and anxitety issues and has had a drinking problem for about 1y . She has at times told me she has suicidal thoughts, she tells me she's a different person with different people, she hates her body, hates her father but still goes to see him, then tells me how hurtful he is to her- one time telling me she wanted to crash her car into a tree because of him, gender confusion etc. I have tried to be as supportive as much as I can.
I let her get away with neglecting to pay rent, only $50. I feel bad asking for money from my child, but also I think it is the right thing to do. I let it go thinking, well as long as she saves and is responsible. But she is drinking in excess of $200 per week. I took her to the dr and she has medication. The dr advised her to cut down the alcohol. I've tried to be encouraging. If she she drank one bottle less than usual, I tell her thats great see you can do this.. go for a walk if you aren't feeling great etc... but she doesn't seem to be making much effort. I've tried being firmer and saying you have to cut down, it's not ok for your health and it will only make your depression worse and it's not ok to set this example infront of your brother(13) and sister(15) so then I get- 'all I want is support'... unfortunately I am at work when she drinks, I work nights. I am in negotiations with my employer to move to day hours to deal with problems at home.
Tonight I got home and my 15yo asked how work was, as she always does. I talked about how there is a girl I work with who kept me talking for ages before leaving, telling me stories that were outrageous and seemed made up, and I said about how strange that is, that I've met a few people like that...etc just general conversation. Then my 22yo starts arguing about what I'm saying, telling me I think too much about things and its not fair that I vent to my children etc..claiming that she has been my therapist all her life...
I decided to stand up for myself and told her I've had to put up with far to much from people in my life, and I'm sorry life hasn't been perfect but I've done the best I can, I don't deserve to be told what I can and can't say in my own house anymore, if you don't like it go. She said don't worry I'm working on it.
I just don't know where this is coming from. I'm wondering if the alcohol is part of this? The attitude has been getting progressively worse, particularly after a relationship she had with a girl- who insisted on being refered to as a him- then insisted on being a non gender 'them'. The gender cofusion stuff started with this relationship. She gets angry if I happen to not say or use the words she expects, or react how she wants. This is very triggering for me, I struggle when I feel I'm being 'micro managed'. It makes me feel like everything I say is offensive and I don't know what to do.
She was nasty to me in her late teens, but this is different. There is an arrogance and selfishness and grose sense of entitlement to her behaviour. I don't think I deserve so much hate and hurt, when I've done everything I can to try to help. I was abused as a child, I have ended up in abusive relationships and now I feel abused by my own child. I'm tired of having to tiptoe around her critcising me. Feeling very confused and hurt.
I have ptsd and have medication.
I am fairly isolated, and have no one to talk to. An outside opinion would be helpful. Thankyou.