It is not certain whether the one you have now is the one you will be with for the rest of your life... There's even no guarantee if the one you just met is the one who will love you forever... Coz' there's no such things as the ideal man or woman, no such thing as the right person, or the right one. It is us who can make love to last a lifetime. So if somebody asks you, is s/he the right one? You can answer, "I'm not sure, but I intend to make him/her my only one."