Tris, I can only imagine how it must have made you feel .... but isn't it better that your girls didn't freak out? It doesn't mean they want to be with you less ... they just don't understand all the implications at their ages. I'm sure there are tears in the future, but I'm sure you'll handle those when you get there; better to not have to deal with their pain right now when you're still trying to balance your own emotions, yes?
Anyhow, there is no "one size fits all" with this stuff, as others have said. I would like to heartily second what Puppy recommends above, especially as respects compassion vs. support/enabling.
"Show me a completely smooth operation and I'll show you someone who's covering mistakes. Real boats rock." -- Frank Herbert