This is common, so don’t feel weird about traveling to Bonaire without a dive buddy. The island is well geared up for you and as a matter of fact, I am the only diver in my travel group so I understand this problem well.
Choose where you will stay and/or what dive operator you can use and ask before you book as to how they can help you find a buddy. Many of the these entities have some kind of system where you can leave your contact details around for others. It would be rare for a solo traveler coming to Bonaire to have some kind of ill-intent, but remember what you were told about meeting up with strangers as a child.
Also try Facebook groups such as Bonaire For Divers. I also sometimes just go on boat dives and get paired up by the divemaster. See ‘East coast‘ question for a unique boat option that works for all divers including those travelling alone.
This question was for some reason often answered with a recommendation from others of staying at Buddy Dive, as if by name that locations was meant just for this. Buddy Dive is a fine place to stay and does have a chalk board where you can sign up and put your contact details on, look for buddies, etc but it’s just another hotel among many options. Dive operators such as Dive Friends Bonaire have location outlets that are not always located at hotels and these work too.
Kudos to the Buddy Dive marketing team for choosing a name that attracts lone travelers anyway.