Bummer. It is nice to be the one with the real bumper though, isn't it.
Do check into that Diminished Value (and I think you have to bring it up to the insurance), as even though this sounds to be cosmetic damage, it still generates a mark on the CarFax report, which is an immediate hit to the resale value of your truck. You probably won't get back what you've lost in resale value, but it'll be at least a little something.
I went through this a few years ago, and would have been better off just letting the girl's dad settle with me, but it is what it is.