I need to find a horror movie i watched like 2 years ago on netflix and i only know the plot

It was a horror maybe psychological movie . The characters were a boy and a girl living close to each other but strange things started to happen to the girl ( like seeing things or the room started to get greener or deformed ) they used to spend a lot of time together . The ending was that The boy started seeing a psychologist and actually the girl was only his imaginary friend and ( i think only ) she killed herself when she found out that she doesn t actually exist . I just think it was spanish but i m not sure also . I m tryna find it so hard