Help!

I'm having a situation here and I can't quite wrap my mind around it. There is a house identical to ours right down the street that is also for sale. They are asking $40 thousand more than we are and it sold! That house is much closer to the proposed freeway than we are. How could this happen? I am stunned beyond belief. One thing's for sure...we are not lowering our price any more. I fired off an e-mail to our realtor to help me make some sense of the situation because frankly, I'm at a loss.