Petty Officer Saman Gunan, a former Thai navy diver in his late thirties, died on 6 July while helping to re-supply the cave with new air tanks.
He ran out oxygen and lost consciousness.
BBC Thai spoke to his family after his death.
"I really loved him," his wife Waleeporn Gunan said. "Every day before he left for work, we said we loved each other. At midday, we'd text to see if the other had had lunch.
"I want to tell you honey, you are the hero in my heart, you always were and always will be."
