Find a red poppy flowerin Minecraft and use the item. It will act as a spawn egg and make the girlfriend appear.
When she is spawned she will walk around quietly for a while before starting to exchanging some words.
Important note: If you exit a world where you’ve spawned a girlfriend and return to it again she will wear the same skin as a cow. You can respawn her again using another red poppy flower to make her have her original skin.