Just to add a suggestion to ways to avoid this bug. To make sure your sim gets enough rest, sleep for part of the night, then nap for the rest. Napping on any bed has never resulted in this moodlet for me. Also, if your sim goes to bed very late in the night and wakes up on their own because it's morning and not because their energy bar is filled, they don't receive the positive moodlet or its corresponding invisible negative counterpart. It requires a little management, but isn't the whole game about management?

An expensive bed is always at the top of my "to buy" list, though. Permanent solution, that. I really hope the new EP or the update that will no doubt come soon after its release will solve this.