Please find a reaction I draw in the attachment. It is a classic example for Robinson annulation.
The Michael part is straightforward.
In the attachment, I also included 2 possible aldol products.
A is commonly regarded as the correct product. I also agree with it.
B is my personal creation. It also form 2 six membered rings
My suspicion that the last product from B is not formed is due to the severe steric hinderance. But on the other hand, the conj double bond have to be on the same plane and the left part of the 3 carbon can form a chair conformation...as the 3D structure I imagined the last.
Any help is appreciated