brightstar, I don't think I've encountered any of my ex's sending me flowers every time I had my period. I find that bizarre.
You may "know" that he is real as in his name, face all matching, real. But, I doubt in 4 months you know that "he is real", as in intent, married, single, 34 years of age, if you were the only one he Skyped, sent gifts to, was going to get on a plane to meet. His accommodation would be nil, mostly food nil, for some flowers and a bracelet.
You kept him up, he has to work, until 5am. You're studying, he has a job, probably successful enough, maybe he saw that this would be an ongoing thing and not what he set out to do.
I smell a rat. Any man that can try the " I had booked a flight to see you" and then ditched you, suggests to me the blame game, his way out.
You don't owe him any letter what so ever.
Be careful in the Internet Dating World.