Hello Dom. Welcome. I agree w/ you as well that some mothers do take that "I'm fine, so my kids will be fine too" approach. As for my W, her stance is "D will adjust. She's very adaptable." That makes me sad.
Bizarre, I may end up saying something of the sort to my W, but I won't do that now. Right now, the path my DB coach and I have set is for me to simply go dark w/ her as best as I can. I'll have to contact her in some way about seeing my D again, but I'm avoiding "small talk" w/ her and riding things out. In the end, at the 11th hour, I may very well say something just like what you suggested. If I need to do so and it still doesn't resonate, at least I can say I tried and didn't leave any cards unplayed.
However, until then, I am still sad. I need to get to the gym today to remove some of my blues. I skipped going last night which didn't help my mood.