Randim,
I did bone up a bit on your posts. We are of the same generation. Although I am thoroughly in favor of respecting the feelings of an SO especially when not told to start with, secrets like ours are not the kind of thing that we talked about ever, ever, ever! From the earliest age, this was something you kept as a secret to survive. I think at some point, her anger at finding out about the secret has to be channeled to something else. She is an adult, she could have left! If you are truly friends and you stay together, you forgive and let go of some things. You had to let go of her affair, correct? Well, you said the relationship wasn't perfect, I get it. The thing is, I think you have to give serious consideration to finally letting go of the guilt for being trans. You did not cause yourself to be trans. It wasn't your plan at 2 years old to pull out the old trans card to cause yourself massive guilt and mess with your SO! It is a part of your makeup, as it is mine. You can run, you can hide, but it will always find you because it is you. My experience says, you will only find peace in yourself when you accept that you are a little different than you were 'supposed' to be (as set forth in Home and Garden) and that that is okay. That said, there is no reason to take being abused by anyone including her.
Moni