Saudade

 'Saudade (English: /ˌsaʊˈdɑːdə/,[1] European Portuguese: [sɐwˈðaðɨ], Brazilian Portuguese: [sawˈdad(ʒ)i], Galician: [sawˈðaðɪ]; plural saudades)[2] 

is a deep emotional state of nostalgic or profound melancholic longing for an absent something or someone that one cares for and/or loves. Moreover, it often carries a repressed knowledge that the object of longing might never be had again. It is the recollection of feelings, experiences, places, or events that once brought excitement, pleasure, and well-being, which now trigger the senses and make one experience the pain of separation from those joyous sensations. However it acknowledges that to long for the past would detract from the excitement you feel towards the future. Saudade describes both happy and sad at the same time, which is most closely translated to the English saying ‘bitter sweet’.'

'..a yearning for a happiness that has passed, or perhaps never even existed.'

Nostalgia for a past, inhabited by people, places, objects, that perhaps never even existed.

Reading Dickens and longing for the wild and overgrown dusty Kentish lanes that were never actually experienced.

Looking at photographs, lived in, experienced, how can the feelings evoked be expressed?