If you can afford it, you can get a Tempurprdic or Sleep Number bed that will raise the top half of the mattress. It will also raise the lower half if you want. At least for Tempurpedic, it's not the mattress but a mechanical platform that the mattress sits on. And with Tempurpedic, you can get a "split king" so only one side lifts at a time.

Again these are pricey but well worth it for what you describe. Hope that helps.