Seeing a lawyer is for your piece of mind and to protect your interests. He/she will be able to tell you what to do and not to do in the interim period. No one has to file. It's just risk management. If you wait till you are served papers, you may get caught with your pants down.
OK...LRT a little modified. Please don't give her exercises that remind her of the past. At least not for now. One of these days she'll have to put on her big girl pants and not fly off the handle when negative emotions arise.
OK. She wants to work on it "this week". Next week may tell a different story (if I'm reading your posts closely enough).
I suggest you live in separate households until she's real clear about wanting back into the marriage. I suggested 6 mos. This may sound a bit drastic. But why not try dating for 6 mos and let her get all hot and heavy for you, sneaking in sex when you can, and then have her beg you to move in cause she can't get enough of that Gogofo love. ;-)