How do you know they were gay? Statistically, I think I must have hosted people who were gay, but none of my guests have (very reasonably) shown the slightest interest in discussing their personal arrangements with me. Well, beyond using the terms "boyfriend" and "girlfriend", and occasionally "partner" in emails.
Sidebar: it's curious how the somewhat cutesy terms "boyfriend" and "girlfriend" have gained such general currency. People of a certain age might remember when terms like "gentleman friend" were still used.