The games that try to communicate deep romantic love are piddling at best, because they are based on a fantasy. The closest thing to a real relationship in a video game is a dating sim where your character builds up a gradual relationship over time and they have conversations and help each other with problems. I still haven't finished Dragon Age but I can believe that it includes these aspects of a romantic relationship. Even in these games, it seems like every conversation option makes or brakes the relationship (or gets you favor points).
In real life, romantic relationships contain more instances of mundane activities and conversations, like what to have for dinner or what kind of car insurance to get. Obviously, in a fantasy world, players don't have to worry about these things. The most mundane part of the relationship, in a video game, might be travelling together, or buying something for the sake of the relationship (self-improvement objects or gifts). In video games with conversation options, the player has time to contemplate them--nothing is said in the heat of the moment, and I don't think I've ever seen a game where a character's crankiness changes based on hunger or tiredness.