When you describe the one true ship 

When you celebrate your ship with other members of the ship

When your friends inspect your fine endgame canon ship

When you have too much faith in the writers handling your ship

When your friends notice how beautiful your ship is

When your ship is in trouble

When the writers hate your ship

When the writers realise they made a mistake by ruining your ship

When your NOTP is the most popular ship in the fandom

When your ship is long gone and deteriorated into the abyss of the ocean