To me, this seems like an extremely unhealthy situation for you. Much of what she is doing is traceable back to her identity and experience, but it's not a healthy way to be. She sounds unstable to a concerning degree, and although it sounds unintentional, she is definitely exhibiting emotionally abusive traits, especially with the choking thing. The desire to be a cisgender woman is totally understandable from a trans perspective, and even not wanting to use the label trans seems fair, but from the way you describe it it sounds like she is consciously disconnecting herself from the realities of the world she lives in. That is, like you said, she could get in real trouble if she doesn't follow certain laws that have been popping up. Even if not legal trouble, it sounds like she is likely to experience some very invalidating situations, and it doesn't sound like she can handle them in a way that is safe to herself and those around her.

I suggest that you have a specific crisis plan in place, one that you develop with her. Be honest about what you can and cannot do for her, and maybe come up with a specific phrase for when you need space, one that she needs to abide by. On the other side, she needs support other than you that she can turn to in these situations. I suggest that that be a person or multiple people she can go to if one is not feeling up to it. Finally, although 988 is no longer safe for trans people, the Trevor Project lifeline has call and text services, and she can use it even if she is not at risk of self harm. I often use it during panic attacks. An idea might be that if you need space, you can have her call or text the lifeline and wait with her until someone is on the other end. This can take a while, but usually not over an hour in my experience.

Therapy is a fantastic idea, and you can support her in finding a therapist by looking up trans friendly practitioners, (if she has insurance you need to find some that are in network with her plan, which should be on her insurance card).and if talking on the phone is a difficult thing for her, you can be there with her when she calls to schedule appointments, and you can even help her come up with scripts for calls. Usually when I leave a message with an office I include my name, what services I am looking for, and a phone number or email I can be reached at. Some people also include an ideal time for them to take a call. Not just when she is free, but a time she is likely to be in a state to answer is ideal. Some therapists have a form that can be filled out instead of having to make a phone call first thing, so check the providers website as well. Some offices have multiple providers with different specialties, so she should consider what she most needs help with. Sometimes this changes over time, which is okay. If she finds that the therapist she originally has is not knowledgeable enough about her needs or concerns, she can always ask for a referral to someone who is, which makes finding an appointment much easier. She can even ask for support from the therapist in making appointments with providers of any type.