For a woman caring for 5 children, making the opportunity to get together with an affair partner takes thought and coordination. The kids have to be out of the house, or asleep, the WW and OM have to be quiet and sneaky, and she has to be willing to face the kids the next morning with this secret. Even her relationship with the kids is being damaged, because shameful secrets stops loving communication.

I agree with the others, that exposure is necessary, and the kids are your most influential potential allies. If she truly wants to avoid more contact with the OM, then she should surround herself with the kids. The 10 year old can be with her until bedtime, then she can have a couple of the small ones share her bed. Heck, it can be hard for a married couple to finagle enough time and privacy for sex with five kids in the house. If she stops plotting to get the kids out of the way, her opportunity for adultery diminishes. She should be accountable to you, and to the kids, for her behavior.

Do you see the point, that she has been actively making opportunity for alone time with the OM? It is not something that keeps happening "by accident".
FBS- me, 53
Married 34 yrs
DD 27 and 30, DS 19 (disabled)
after 2nd DDay, filed for D Dec 09 (me)
6-6-10 WH moved in with OW
7-3-10 WH returned home
taking recovery one day at a time

"Forget the former things;
do not dwell on the past.
See I am doing a new thing!
I am making a way in the desert
and streams in the wasteland."
Isaiah 43:18-19