Any suggestion on this

 

Two weeks ago a person asked me to help her with a small project since she liked my previous work. Due to some reasons, the most important one was the price, I guess, we stopped to email each other and negotiate. Today I got an email from her and she told me there was a possible project from another company and gave me the contact email address. How can I reply such an email? Should I only thank her for the information or should I mention the negotiation as well? I am OK with lowering the payment a little bit.

By the way, this is an American. 

Thanks for your input.