However, despite the gift, German media claimed that Lubitz's relationship was in trouble and the couple may have split up.
This has been seen as a contributory factor to Tuesday's tragedy.
The woman, who has not been named, is understood to be staying with family while German investigators conduct a full forensic search of the property in Dusseldorf.
The couple lived in a smart top floor apartment on the outskirts of the city.
Habibalah Hassani, 53, who runs a pizza restaurant close to their flat said he had often seen them together.
'They were a very nice, friendly young couple. She was a polite and attractive woman. They would come in once maybe twice a week.
'He used to tip well, he was very generous. He had told me about his trip to San Francisco. I hadn't seen them for a couple of months before this happened.'
Another neighbour who declined to be named confirmed he lived at the flat with his girlfriend.
'I think she will be with her family grieving at the moment. It is very sad.'
German media claimed that Lubitz was receiving treatment for depression and had been certified sick on the day of the disaster.
Ralf Herrenbrueck of the Dusseldorf prosecutors' office said the discovering of sicknotes inside the property 'support the current preliminary assessment that the deceased hid his illness from his employer and colleagues'.
Mr Herrenbrueck said other documents found he was suffering from 'an existing illness and appropriate medical treatment'.
Prosecutors claim they have not found any evidence linking Lubitz to terrorism or any form of religious extremism.
The thorough search has failed to find any suicide note among dozens of boxes removed from the apartment and Lubitz's family home in Montabaur.
Meanwhile, it has emerged that Lubitz knew the area in the Alps where he crashed the Airbus A-320 because he used to visit the area to fly gliders.
Dieter Wagner of Montabaur flying club said: 'Andreas has participated in one of his courses in the Alpes-de-Haute-Provence with my niece, who was a good friend to him. He was passionate about the Alps and even obsessed. I'm sure he knew the area of the crash well because he had flown in a glider.'
Ernst Muller, also a member of the club added: 'I am certain that Andreas has participated at least once or two internships with us in Sisteron (Alpes-de-Haute-Provence)'.
- Daily Mail