i agree with most of you, that Charlie's response was quite wrong. he shouldn't be so calm about it. okay, even if he just need-to-know, he should at least be a little bit angry at Bella, or Edward! like how he reacted when Edward told him about the plane tickets that Esme had given Bella for her 18th birthday. even if Jacob had prepared him, he should at least screamed something to Bella. that's just only right reaction from a parent!
but then again, he couldn't have done anything. Bella is married to Edward, so he sees her as an adult now. plus, what some of you have mentioned about the time he told Bella like he would lose her anytime soon in Eclipse, maybe he did know something was going on, something extraordinary. but he didn't wanna get too much involved, because he's those simple-minded people who wants to know less. and because he trusts Bella so much, he didn't want to question her.
so i have just cleared my own question on Charlie's reaction. haha! but i'm still not that satisfied with his reaction, and i'm not gonna let it bother me. for now, at least.