IMHO a better description for this thread might be "Buddy diving on Bonaire for a solo traveler". This is quite different than diving solo on Bonaire, which some people also do. Diving with an established buddy pair as a newly acquainted 3rd diver falls somewhere in between both on the risk vs. benefit scale. In most situations the neophyte lone diver benefits at the expense of incremental risk and responsibility for the buddy pair. But it certainly is a friendly thing for the buddy pair to do.
I really like the previous suggestion to participate in a group trip with other solo travelers. This provides an opportunity to buddy up with someone of similar skills, comfort levels, and air consumption rates before committing to any particular dive profile or activity. Posting inquiries in forums like this, or on BonaireTalk, prior to a trip might also yield a qualified buddy.
I also agree with the previous observation that the resorts that have the most divers wandering about are probably least attractive to budget-minded lone travelers. Bear in mind that you don't have to stay at Buddy Dive or Captain Don's to enjoy meeting people at their happy hours. Customers staying elsewhere are always welcome at the dive resort bars, restaurants, and dive shops.