n2l -
I did not set any conditions for her nor did I mention that I would have no contact with her. This is,I suppose, only part of a plan B letter.
I would disagree that this was part of a Plan B letter. A plan B letter, as I understand the concept, specifically tells the WS that you will no long have any contact with them (short of any necessary interaction regarding kids and finances, and even that should go through a 3rd party intermediary if at all possible) until such time as they are willing to meet your conditions for working on recovering the marriage (NC letter, counseling, etc).
Plan B is intended to follow a good Plan A, if the affair is still ongoing and/or the BS is beginning to lose their love for the WS.
I'm not familiar with your situation, so I can't ascertain as to how long you did Plan A, or how effective you thought it was.
Your wife has left, with no apparent intention of coming back. I would suggest that you contact a lawyer (if you haven't already), get your finances separated and everything else you need in place to protect you and your family from your WS.
I feel a full plan B letter would make my WW think that I was colluding with the kids in a plot against her.Any thoughts?
Stop worrying about the effect your actions to protect you and your kids will have on your WS. She needs to suffer the consequences of her choices, and you need to set some very firm boundaries in place if you haven't already.
Write the Plan B letter. State your conditions for reconciling the marriage. Send it. Then stay dark. Very, very, very dark.
Work on you. Be the best person, best man, and best dad you can be.