And when presenting this do NOT apologize... This is HER mess...
Speak to her the same way you would a destructive teenager you CARE ABOUT...
Do not speak patronizingly, or arrogantly...
Speak with calmn, confident, educated consequence focussed dialog only...
"You have a choice to rebuild a marriage here or to tear a home, a marriage, and a family into pieces that you have to live with for the rest of your life. I have made lots of mistakes and so have you, I am NOT going to ruin children over that... YOU ARE... or you are going to stop this nonsense and work with me and a therapist to rebuild this into something good and healthy for both of us."
Don't say "what's it gonna be" just offer silence... she will fill in the blanks
You walk away... do NOT SYMPATHIZE with an addict, you state the situation in simple terms, cut off their addiction supply lines and wait for them to run to the streets or to agree to rehab
NO SYPATHIZING... you say it simple, factual, and with care...
Your wife is gonig to cry, threaten, scream, throw things... she's an addict and she will manipulate you into a codependent situation as long as you ALLOW THAT...