Thank you for all your comments. It's reassuring to know that at least my bag will eventually show up. I'd had similar experiences with QF & CX in the past, except they were able to locate my bags, and they showed up the next day. This is probably why I've never really thought about buying a travel insurance. But yes I have learned my lesson, I will make sure I do that from now on.
Rankourabu, would it possible for you to share a bit more as to how the bag eventually turned up? did they contact you or anything? or did you try to call their customer support? Many thanks