I understand the kind motives of the people who suggested that the OP just put up with it. I agree that Ben's seeking personal validation by having people admire his vacation pictures.
But...IT'S. NOT. WORKING.
Ben is using an ineffective strategy that's having the opposite effect.
Perhaps it's time for what my family called 'A talk from your Dutch uncle'. That is, a kind, loving but frank phonecall on the clue telephone. In the long run, a Dutch uncle talk spares a person a lot of hurt, because it presents them with the information they need (but lack) to meet their goals.
'Ben, you do a great job of taking pictures. But do you realize that by now, I've seen thousands of pictures of X island? You're overestimating how many pictures people want to see of the same place. You need to take some photos of other places to share, if you want people to look forward to seeing your pics. Or join an photography club, and meet people who really adore looking at photos, more than the average person. The average person wants to see about 20 pics at any given time. Please don't ask me to sit through a showing of ten times that.'
Have you ever suspected that Ben might have Asperger's? I say that because my sister does, and this sounds like something she does: vastly overestimating how interested other people are in her interests. It's something most AS people have to learn by rote.