i cant take criticism..

[Mystic]

so like.. i have been working on a story for 15 years now, i am eventually going to make it into a graphic novel, but it is still in pieces but i am slowly putting it together. i was talking to my friend about my story because she loves books and likes writing, so i was asking for her opinion on a plot idea i had. she didn't like the idea and i was fine with that but then she told me something that made me defensive, she told me that i needed to take writing classes if i wanted to make anything good. she told me that unless i was just was writing it for my self then i needed to take writing classes other wise in her opinion i couldn't write anything worth while. i found that very offensive and all it did was make me want to write my story with out writing classes just to show her she was wrong. i know that taking some classes would just help but the fact that she told me i had no chance of writing anything worth while if i didn't take them was annoying to me... what are your thoughts? i know taking a class would only help but i think she is being a little snotty with the idea that no one can write a good story with out training. i guess all in all... she made me feel like i am to stupid to write a story... grrr...wah wah wah..