You can allow panic to override logic and that can allow you to do pretty much anything to try to stop the D and convince your W that she needs to stay with you...
And if you choose that route, that's OK. In the sense that it is very normal and natural and hey... sometimes, that works...
Yet, that's probably not a M that either you or your W would want to be in, if it DID work...
In the mean time, you can work through the pain and loss of an M that is now dead...
And stay on a DB path... and maybe... as you work on yourself and become and even better person... better father... and likely a better partner...
Your W may choose not to be a fool...
Just because your W is dating doesn't mean she'll find someone remotely as good as the man you are becoming...
And just because the D process has begun, does not mean it will be stamped...