For a Woman (2013)

After the death of her mother, Anne makes a shocking discovery: an old photograph casts doubt on her origins and leads her to discover a mysterious uncle who lived with her parents after the war. As she lifts the lid on a long forgotten family secret, the young woman learns that her mother once succumbed to an amorous passion that was as intense as it was short-lived...

Unfortunately the movie For a Woman is not yet available on HBO Max.