Wonka, this 21st party is the son's fiancee. So her family is organising everything. My son's was last year. It's ok I understand the mix up. :-)
I will be letting the W be the one to file. Again, my belief and value all along was not to initiate anything at all.

As an option: I was thinking the first text to be around the 28th Jan, when she starts the new teaching class for the year.
I was thinking along the lines of: "Wife, I hope you have a fantastic class of students this year, all the best for a good year. HWA".
Your opinion on the timing?

ME:51 W:46
M:25
S:22, S:20
Divorced 16/9/15
BD 10/12
W left 12/12 with OW, affair confirmed Nov/12.
Dark since 6/13
I"m in a new relationship since Feb 14.