If no matter what irritating ting dat person does, rather than seeing it as someting dat bothers you, you see it as someting to over look. If you wake up, go to sleep, and go through di day referring everyting to dat person... If you can't help but to smile everytime you see dat person no matter di appearance.. If you always say to yourself, "Oh, I tink him would like dis" whether it's food, clothes, or fragrances dat you want him to smell on you... If you know dat person like you know yourself and you can't explain how..... Then you're in love....
But of course it should be on both ends of di relationship....