He looked at you and laughed so hard....he is your best friend for more than 10 years...and you started to develop feelings for him and you decide to be brave and propose to him...but he just laugh off and looked at you

"What are you talking about!? We are just friends! Nothing else...stop playing around...I never had feelings for you or even looked at you as more than a friend...stop playing around ok? You're making me laugh"