If the small Scamp bed doesn’t work for you, and you don’t want to split up, there are a couple of options. The deluxe models are wider. I had always heard it was 54”, not 51”, but it’s definitely closer to a true double.
Then there is the Casita
Liberty, which is available in a 16’ length as well as the more common but heavier 17’. Casita
16’s have a lower ceiling than Scamp, so not for taller people.
My wife thinks the small Scamp bed is perfect... for her! We sometimes share the bed for a while in the evening, but when it’s time to roll over and snore, I roll all the way to the front bunk. Space aside, it avoids disturbing your partner for nighttime potty runs.