You two look great together! What a lovely couple! What, you guys aren’t dating? But you two are seen together all the time. Are you sure, you people are just friends? Just because being in love isn’t on cards for you at this moment don’t mean you can’t fall in love. You started off well from being friends to best friends. But there is nothing more to it. PS You do not control falling in love.
Now, if you find yourself doing any of these activities, congratulations you are in love. Admit it or not, your actions prove it. ;)