One other thing to mention is that just about every major dive site on Curacao is also a beach with amenities - including usually a dive facility and snack shop. Most have a beach toy operator also. And a couple like Varsenbaai have a decent waterfront restaurant - in case your wife wanted to go along. You can find out who is where here:
Curacao Dive Operators- Curacao Dive Package- Dutch Caribbean Diving Specials Discover Diving is set up for tank rentals if you're up near Playa Lagun - they have a truck height tank loading area. Besides Lagun, Playa Jeremi is five mins north.
Can't help with the buddy situation. Except to second the Dive Bus. I'm fairly sure they'll pick you up at Floris also.
As mentioned, most beaches have on site facilities and dive ops...
Playa Porto Mari / Beaches / Attractions and Restaurants / Home - Curacao
Overall, here's my standard "Curacao Shore Diving Made Easy For Diver with Non-Diving Spouse" response:
My wife doesn't dive, nor do my two children. Family trips to places like Hawaii or Cayman Islands can be difficult to dive, since diving there usually means being gone before they wake up and being absent for 2/3rds of a day out on a boat. One of our favorite family vacation spots is Curacao. Been there three times, and will be back many more. With plentiful shore diving, most of which can be done from some of the islands nicest beaches, I'm able to get a fair bit of diving in on a "non-diving" family vacation. Goes like this...
Nice, leisurely breakfast at hotel before heading off to a beach like Playa Porto Mari. When we arrive I tell the dive op on site I'm looking for a shore dive buddy and point out where I'm sitting and then set up camp at the beach with the wife and kids. Play with the kids in the sand and the water for a while. Tan, snorkel, read a book, etc.
At some point a single diver or buddy pair will approach me and ask if I want to join them for a shore dive. Before grabbing my gear I turn to my wife and say "I'm going for a quick dive... want me to grab you a pina colada on the way back?" and walk into the water. 45-60min later I'm back on my lounge chair with a cold beer and happy wife. Typically I can get 10 or so dives in during a one-week trip without anyone really noticing/caring that I did a fair bit of diving.
Everyone in the family loves "Daddy's Night Dive" at the Marriott house reef. There's a bar right on the ocean. We sit down for a few drinks and appetizers as the sun sets. When I see my buddy walking over to the dive shop 50ft away, I tell my wife what to order me for dinner and then I head over, throw my gear on, and walk into the water. The kids play "follow daddy's dive light" as we dive the reef that essentially wraps around the point where the bar sits. 45min later I'm back on my bar stool with a cold beer, BBQ ribs, and a happy wife.
And, we've met some great people that we ended up spending time with during the trip. One guy I dove with in Curacao had two kids same age as mine and a non-diving wife. We ended up spending most of the week with them and still keep in touch.