So Fing pissed off CAR Keyed

I was doing a good deed on sunday by washing my girl friends car that i had bought her a while ago. Then come to find out that after i got it clean, i could see a huge KEY scrape along the whole right side of the car and even went all the way up to the trunk. im so pissed, why the hell would anyone do this. Whenever i look at her car i am so mad. Its a 98 volvo so its not worth really repainting the whole car. Any wise ideas please?? its deep in some places and not so deep in others ..to me it looks like a pen with a sharp edge.

 

I sure wish I had an answer other than you gotta paint it. Ive seen futile attempts at spotting the damage but it winds up looking worse