Hi Emma, coming out to my wife was the hardest thing I have ever done. I feel your pain that she is in denial, from my own experience my wife initially stated if I transitioned she would leave me, I of course said that I wouldn't initially for fear of losing her, over time she has realised that if I didn't transition I would be living a lie and miserable, and now can't even remember suggesting she would leave.
I think the initial shock our wives feel takes time to settle. Give her time to come to terms with the news, when she asks questions be honest, understand she is probably scared, and wonders where her future lies, she may need to know you are not going to change who you are, and that you will still be there to love and support her, try not to blame her if she says horrible things to you, she probably doesn't mean it.
I hope things work out for you both
Hugs x