Are they harming you buy talking about this frequently? If not, then who cares? It's their personal quirk. Play along. Let them own this one thing that they have to talk about. Maybe they're insecure and not good with social interaction, but they feel like they have to talk about something.

If you're honestly annoyed by it, then complaining on some random internet forum about it isn't going to fix the situation. Confront the person and tell them directly that they need to find new experiences to talk about or that it's getting on your colleague's nerves.

Stop being a coward around your coworkers.