Horror movie set? Come on, how bad can it really be? Roses are tough plants, they bounce back from almost anything. I've seen some gnarly bushes that still put out flowers when you least expect it. Maybe your cousin just needs to give it time or stop being so dramatic about gardening.
My neighbor's rose bush looked like a skeleton for two whole years after she was too gentle with it. I used to totally agree with burns.terry about roses being tough, but seeing that changed my mind. It wasn't about bouncing back, it was about growing all weird and weak because the old stuff was hogging all the light. Sometimes a hard cut is just basic plant care, not being mean. You have to be cruel to be kind or you end up with a thorny mess.
Talk about a lesson learned the HARD way. My cousin tried that "light touch" pruning last year and her rose bush looks like a SERIOUS horror movie set now. All twisted thorns reaching out to scratch you, with maybe three sad flowers hiding in there like they're ashamed. Guess sometimes you gotta just trust the shears and cut the drama out.