When it comes to love, how you approach the other person tells a lot to you, whether it is love or lust. Love is all about the other person. Therefore person-centered is what makes them happy. However, lust is all about pleasure. Therefore pleasure-centered is what makes me happy.
The easiest way of seeing this is looking at what the person is doing, whether or not they are doing things to make their partner happy or themselves happy. This does not mean that a person cannot focus on what makes them happy, but they will do their best to make their partner happy. This is love. Because love makes you do things for the other person, and when both partners love each other, they do for the other, creating a beautiful relationship.
The one thing that I do know by experience is the one-directional love. And I find this happens so often in relationships, where one person does love the other, but the other does not truly love them back. This makes it difficult for that person to see that what the other has is lust, not love, because their love blinds them. But love means letting go, something I have also learned. And true love is not one-directional. So we need to look not just at ourselves, but at the person we are with. Suppose both parties are in lust and like it this way, great. If both parties are in love, well, that is wonderful. But if it is one-sided, then the person who wants love needs to figure out what they want to be happy, true love, or the person they love. Because I firmly believe that everyone can find love, true love. We only need to look for it, and sometimes that means letting go.