I don't want to think what happened to its head.
But I kept walking. After an hour I could only keep going by walking away from the beach and onto a road, so I headed back. It turned out I was only yards away from Otres beach, where you can buy loose joints for $1.50 (I didn't) and live out your fantasy of reading sacred Indian texts in a hammock (I did, albeit for only about two minutes).
Vedas and (Walmart) Tevas.
On that first day I also visited Wat Krom, which is worth a visit and increased my rating of the place.
The next day I headed out to Ream National Park. A nice combination of boat trip, wildlife (mostly birds), jungle trek, and beach. Better was the next day, when we went to Otres. And best of all was the last day, when we took another boat to visit three islands, which was like the Ream trip but with less wildlife and more beach, but also better beaches, a more interesting boat ride, and snorkeling. If you've never snorkeled, take your glasses off and swallow some salty water. You're welcome.
Some people jumped off the top of this boat into the Gulf of Thailand. Others dropped hesitantly while wearing a life-jacket. I won't say which category I was in, but it wasn't the former.
In short, Sihanoukville is worth visiting after all. If you have just one day do the trip to Bamboo Island. If you have two, go to Otres beach as well. If three, hit Ream National Park. And visit a wat (temple) or two in your spare time.