can you be happy alone?

this is something i've been thinking about quite a lot recently. i feel like recently the trend has been for people to try to normalise loneliness or romanticise being single. the whole 'independent girlboss' attitude for women and the sigma thing for men. but both of these feel incredibly superficial in many respects. its self defeatingly about the appearance of being independent more than anything, ie. the external validation of supposedly being completely content with yourself. i would love to be a person who genuinely does not require romantic relationships or even friendships for happiness, but sees them rather as a bonus. maybe its just me, but i cannot imagine being like that, ever. the thought of dying alone, never having married, never having loved or been loved, childless, pains me. can you truly ever train yourself to be content alone, or does that contradict how we are programmed? does anyone here think they have reached that point?