This is roughly what i remember and understood from the film. I saw it on TV at least 5-10 years ago in a language i couldnt understand. Probably german but im not very sure about it.
A man happens to meet a woman who is probably autistic during his trip to some kind of hospital. The woman follows him to his apartment after his visit. The plot continues where the man travels across the country via train to meet his family members. The woman secretly follows him onto the train much to his dismay. They are subsequently thrown out of the train and have to make the rest of the journey through some other method. When he finally arrives at his destination, the is told to attend a function by his family and he does. However, during the function, he felt suffocated by the atmosphere and company and wanted to get away. He then decided to imitate the autistic woman by screaming loudly in the midst of the function. Some time later, the man is living with the autistic woman and at the end of the film, he brings her to a supermarket and demonstrates to her how to put things into the shopping trolly by taking the item off the shelf, and dropping them into the trolley. The film ends when the woman proceeds to take an egg, and proceeding to drop it into the trolley. The credits roll the moment the egg leaves her hand.