IMHO, the best thing you can do for your daughter is to manage your PTSD symptoms better. By ending the outbursts yourself, you will show her the way to control her own PTSD. Just because you have a good reason for your overflowing cup doesn't mean you can explode unchecked when someone is stressing you out. Don't allow yourself that luxury. Also, there's a good chance that many of her symptoms will disappear when yours are under control. She may be responding to you the way you respond to her; and so, if you begin to respond to her more respectfully - even when angry, then her reactions to your reactions may be easier to handle.
There are rules to living in your house and those rules must be respected. There are consequences for breaking those rules. List out what the rules are, believe in them. Post them. List out what her favorite privileges are and post them to show her you are willing to take those away if she breaks the rules. Then give her 7 free spaces in front of those privileges. 7 freebies. Everyone makes mistakes, and you cannot expect perfection from yourself or your kids. Each time she breaks a rule, let her know that she's lost a space and mark it off. If she gets to the privileges, take the one she values LEAST first... so she can see her favorite ones are really going to be lost if she keeps breaking the rule. Don't sit there in an argument with her, saying "That's one space, that's another, you just lost another, keep going little missy and... that's another one! Do you want to lose anymore?!?!" This is bad. She loses a space, and if an argument ensues you need to give her a time out and take one for yourself. Send her to her room.
One of my rules comes from my son saying "I hate you" to me almost constantly. I felt so guilty, and he would say "I hate you" and I would feel it more than he meant it. He was just idly saying it, using it because it worked, and it was tearing me up. So, he's not allowed to say "I hate you" to me. Instead of getting all stressed out about it, I started responding "Strike" and marking off a space. He stopped saying it. He still expresses his unhappiness with me, but not in that triggering phrase. I can handle the other stuff, but the phrase "I hate you" is part of my traumas. Don't allow your child to push your buttons just for fun. As I said, my son can still express himself.
Take back control over what you have control over, and let go of what you cannot control. Feeling guilty about how you've raised your daughter thus far will only further damage her and your relationship with her. If you feel guilty, then deal with that in therapy. Don't bring it out around your daughter. She's only going to see "opportunity" with that guilt, or she's going to feel bad about herself because you feel bad that she's had it so rough. It's really not about her. It's about you, so you can fix that in therapy.
Let her be responsible for herself, validate her feelings NOT the bad choices she makes. Listen to her and really hear what she's saying. Ask questions, express concern. Then tell her, "I understand that you felt _____, and I get why you felt that way; but choosing to _______ was wrong." If a rule was broken, then give her a strike... if that leads to taking something away then take something away.
I hope this helps. It's very difficult to make these changes, so be kind to yourself (and your daughter) along the way. And get a good therapist to support you while you're working through this. You will lead your daughter out of this through your own recovery. THAT is how you help your daughter.
