A house by the beach, with the dog, tea and each other. If this is the ending for them then it is a good one. They took the right road and found peace and comfort in the days they may have left! Good for them 
I think they finally found their paradise and have realized that no matter what happens, as long as they are together, they are happy. So now...did island go boom boom? Or just one big FAAAHH-LAAAASSHHH forward.