My wife said she was DONE with our marriage, and was openly threatening divorce when I filed. She in fact retained an attorney before I did (although I filed first).
I would describe my approach as a hybrid of what you're calling "confrontation" (and what I would characterize as a tough legal/financial/affair-busting stand) and the softer package of working on my issues (180s, "becoming the man only a fool would leave," self-improvements, etc.).
I do think it made a big difference that I did all of this almost IMMEDIATELY, however, once I discovered her affair.
