One lonely Filipino seafarer in a cruise ship unexpectedly falls in love to his roommate but rejects him, as they sail together to Caribbean he attempts to commit suicide to end his depression.

Great. So our Seafarer is lonely. Good place to start psychologically, as our general assumptions are seafarers spend a great deal of time lone, at sea.

Story Challenge: why might such a lonely man have have made such a isolating career choice - given it's so lonely out at sea?

Still the question of gender remains? Recognise the importance of identity politics, but "he" -> falls in love with ... Who? The value of this question is that of describing Villain - surely the best part of story development. Suggestion: Think maybe 'Film Noir' .... that is if the villain is female.