If you’re a writer and you think you could be in love, E.B. White has a test that might help you find out for certain.
“Let us say you have sat down to write a letter to your lady. There has been a normal amount of preparation for the ordeal, such as clearing a space on the desk … and the normal amount of false alarms, such as sitting down and discovering that you have no cigarettes. (Note: if you think you can write the letter without cigarettes, it is not love, it is passion.) Finally you get settled and you write the words; “Anne darling.” If you like commas, you put a comma after “darling”; if you like colons, a colon; if dashes, a dash. If you don’t care what punctuation mark you put after “darling,” the chances are you are in love — although you may just be uneducated, who knows?”
via: How to Tell Love From Lust on Brain Pickings