I think it is important to focus on her feelings more than her words at this point and time. With that being said, if you start to write down some of the things she is saying, you will probably notice a common theme (lonliness, self-doubt, finances, etc.) Once you understand the feelings behind your words, you can slowly begin to add "I know that you might be feeling ____" into your conversations. I highly recommend the DB book and another one called "How to Improve Your Marriage Without Saying a Word." Other ideas that comforted me early on were the movie "Fireproof" and the related book. Regarding the ring... follow your heart and keep it on. Taking it off will signal that you share her thoughts about your marriage and might help her justify that the marriage is over because you have thrown in the towel, too. Give her space and let your actions show her that you love her.
