What a sensitive age regardless! At least he is letting you all know what is going on with him and that he isn't hiding. I used to hide.
Ah to get your heart busted, its the worst thing in the world. Luckily it is the summer and he won't have to see her in school everyday. That would just be torture.
Just because he is 17 doesn't mean you stop being a mama bear.
Keep us posted and let him know he's got a whole bunch of people thinking about him.