Hi Sweetpea,
The first part of post #2 here has more information about some of the ways that can help accommodate a couple where each one’s need and preferences are different. A split layering is certainly one good option that has helped many couples in a similar situation although there may also be “regular” mattresses that work well for both of you as well so I wouldn’t rule out a regular mattress either … especially if you have researched and are working with a knowledgeable retailer or manufacturer (step 3 of the tutorial post here) that has experience in dealing with situations such as yours.
Phoenix