I have this really pretty and smart

I have this really pretty and smart friend. Lots of guys ask her out and she always gets straight A's. I think she thinks she is perfect. She always shows off, but so subtly, that nobody besides her closest friends notice it. Well, whenever I screw up, even just a little bit, she's there to give me a 10 minute lecture on how to be a better person. Her lectures are so annoying! They are full of "you shouldn't be doing this" or "I don't like the way you are doing this." I'm sick and tired of it. I've endured this for almost 2 years and I've told her in the past to stop. She makes feel like a horrible person and she always says "this makes me not want to be your friend" and that makes feel like trash. It's not like I don't know my own flaws, I try to improve on them. She just keeps repeating her lectures. So yesterday I told her to stop because she made feel like a bad person. Guess what she said? She told me if I didn't want her to lecture me anymore I should stop screwing up. I tried to get through to her and she ended up crying saying she was only doing it for my own good and that my words made her feel like a bad friend. I was only standing up for myself and being honest with her. I've tried to talk to her to resolve this, but everything I say, she has something to retaliate it with. What in the world do I do????