I have been doing that but I also feel like that is reinforcing her coming to me with her woe is me stories. I am afraid that if I don't validate her feelings, it will trigger her as I have done before.
THIS is the mechanism that keeps the whole game running. "I am afraid that if I don't... . " And that is why you walk on eggshells and she runs the show. Communication is important, but you have to decide, first, that your life and freedom (and not enabling her) are more important than staving off her explosions (which, honestly, will still come, won't they?).
My uBPDexw would do that kind of thing to me. I eventually stopped replying, unless it had to do with our children. I stopped reinforcing the "I'll run to him whenever I hurt" thing she was doing. If she ever confronts me on it, I am just plain and unemotional about it... . "I read what you wrote... . I just was too busy at the moment to reply, and I feel for you but just didn't want to reply." No explanation needed. You don't need to justify not wanting to get sucked into the vortex. You don't even need to explain that the vortex exists ... . they certainly won't hear it, they will just argue with you about it.
Here's the absolutely crazy thing that we either forget about or fail to realize in our quest to avoid their temper tantrums and painful behavior: we have a right to think and feel as we do. That is what it means to have our own identity. You have the right to say, "I didn't want to reply to that." And you have a right to do it WITHOUT having to answer to them. Are they your god? Do you answer to them?