I agree, Afa. The L appointment is necessary. She'll move out but I doubt she'll initiate D proceedings, so "let the dust settle" as my coach said. Tell her you get it, that you understand she wants a D. Let her find her place and let deal with the initial stress of the finances. She might have to get a new job. This is what she wants, correct? So let her deal with the consequences.
My coach said it's important that she feels that you're letting her go. Then she'll stop trying to pull away from you. Remember, things could change, but you must let some time go by. Careful saying anything that might make her feel like she's a bad person, or she'll pull away even more. Good luck.