I am a solo traveler/diver and I have stayed at Divi twice. There is no single supplement which is nice. When I was there, there were 2 dive groups, each of which had its own boat. I was on what I affectionately called "the leftover boat". I enjoyed it because we only had between 4-7 divers/snorkelers on the boat in the mornings, so it was not crowded. Last time I was there, I was able to hook up with some people for afternoon dives off the house reef. This trip, I wasn't able to do that, but we had enough people on the leftover boat to do 2 afternoon boat dives. However, I was graciously accepted as an honorary member by one of the dive groups on their afternoon boat, filling in for the divers who wanted to hang at the pool and drink all afternoon. I did a few night dives on the house reef with that group as well. Long story short, I had no issue being a solo diver.