It WILL come out at some point, probably sooner than later because I feel it's important for her to understand that kids want an affectionate mom all the time. And if it helps me in the process, well that's a bonus.
You get something on your mind and you won't drop it. The only reason it WILL come out at some point is b/c you keep it burning in your brain. I think you are using the non-affection toward the kids as your ticket to approach her and hope you get rewarded with ML, to boot. It won't happen buddy, not that way, and you better let it drop.
I wasn't as affectionate with my kids when they were as old as yours are now. I was when they were little, but when a boy is 12, he usually doesn't want mom slobbering all over him....
Just don't go looking for trouble. I get the feeling that's your biggest problem.
It is not about what you feel should work in your M. It is about doing the work that gets the right results. Do what works!