Like more of caring romantic signs you have for that SO, not nasty display of affections or you prefer to keep that for yourself and your partner in private as noone has to know you are dating someone or have a SO, taht is yoru business not the public business. Would you behave the same if that partner or SO is not really a serious partner, you are just dating that person but the relationship is not really serious but you two do hang each other an may even be living together.
For example celebrities or movie stars. I dont know if they do that just for PR committments or stung or what. Like one actor is dating another colleague but they dont want the public to know they are dating or that they even in a relationship (what is wrong about people knowing you love someone, I mean taking aside that person is anotehr actor , it is just a human being anyway), so they are never are seen in public together as a couple, never. For example like awards shows or movie premieres one of them always is alone at those events, they never bring their SO with them to join on the event, as they are like hiding their relationship, they prefer never be seen together. On the other hand when there are photos of them on social media that go viral on a more private scenarios such as private parties with friends or birthdays they are seen together, isn't that contradictory. ALso the paparazzis had caught the couple together on other places but on public events neither one brings the other to be with them.
Why to hide the affection or love you have to another person? Or could be becasue the relationship is not serious even if they had been together for a while and even live together. This happens to a actress and her current beau, who is also an actor they are never