The difference between XIV and the singleplayer Final Fantasies is, this is an MMO.
In the singleplayers you are controlling a premade character/party with all relationships and bindings etc., while in a MMO you are controlling the charater which represents yourself in this world.
The Dev team will never enforce more closeness then friendship or trust, just like you don't want to fell in love for someone just cause i as the Dev decided so...