Well, 'The Long - Distance Love That Couldn't Bridge the Gap' is a great title. It shows that the distance was too much for the love to overcome. 'Love's Long - Distance Demise' is also suitable. It implies that the long - distance aspect led to the death of the love. And 'Far - Away Love: A Tragic Tale' is a simple yet effective title for a tragic love story involving long - distance relationships.
Some good titles might be 'Love Lost in the Distance: A Tragic Long - Distance Love Story'. This title not only mentions the long - distance but also emphasizes that love has been lost. 'Long - Distance Heartbreak: The Tragedy of Separation' gives the idea that the separation due to long - distance has caused heartbreak. 'A Love's Long - Distance Tragedy: Fated to Fail' makes it clear that from the start, the long - distance love was doomed to be a tragic failure.
'Love Across the Miles: A Heartbreaking Separation'. This title clearly shows that there is love despite the long - distance, but it also implies that the separation is causing heartbreak. 'Distant Love's Tragic End' is also a good one as it tells that the long - distance love has a sad conclusion. Another title could be 'Long - Distance Love: Fading into Sorrow' which gives the sense that the love is gradually disappearing and turning into a sad state because of the distance.