again, why are you trying to buy her the most expensive iPhone in this comparison? Buy her a cheaper one if that's the phone series she likes. a 128gb iPhone 7plus isnt $1000 as it is, its $880, maybe with tax and fees you'll hit 1k, but then you'll be paying tax and fees for the other phone too.
Also, if you are that worried about her losing stuff, get insurance on it.
This, or just get an older iPhone -- not like they're going to be playing bleeding edge games. I'm still on a 5S and it works fine.