You say your bf is not comfortable with long flights, he has never taken a flight longer than 4 hours and I guess he does not like even a 4 hour flight, does he not like flying in general or is it the fact that sitting in a plane is never comfortable and the thought of 14 hours of it is putting him off ?
It is not easy to fly long distances but sometimes it has to be done. There are more things on the plane to help the journey pass, the in flight entertainment, movies etc. meals are served which help break up the journey, you can still of course read. It is a lot easier on long flights to get up and walk about, I always take an aisle seat so it is easier to get up without disturbing anyone else and take frequent walks around the plane.
Tell your bf to make the flight part of his adventure, try to relax and enjoy the experience, it is well worth it.
I hope you both have a lovely time together in Philippines.