Oh goodness, STFU, and you are not abusive, that would be the full plate of irony.
Context is a funny thing, what I might consider abusive someone else may not. The problem is there are two phases to communication, sending and receiving. Your intent may not have been abusive, like with the STFU, but the perception might be very far off, like with STFU. So even though you did not see a problem with it, as fixed in your belief that you were not abusive, she may be just as fixed in her belief that you were.
If there is no walking away from this divorce, if you cannot convince her of your intent, or get her to try, at some point it is time to say, ok this is going to happen, and you have to protect yourself.
If she wants a divorce, proof of emotional abuse will be meaningless, and lack of that proof will not stop it. Might be time to get a lawyer, and start preparing for what might be the inevitable.