Hi gusbuf,
I’m sorry to hear that your mattress isn’t working out for both of you as well as you hoped for but at least you had the foresight to purchase a mattress that has a good return policy so that you could try it out without any risk.
There will also be a break in and adjustment period for any new mattress or sleeping system as the mattress loses any of it’s “false firmness” and the cover stretches and loosens a little and the materials settle and your body gets used to a sleeping surface that is different from what it is used to (see post #3 here. This would typically be a few weeks but it can be shorter or longer depending on the specifics of the person and the mattress (higher density materials like latex can take longer) and it can be surprising to many people how much their sleeping experience can change over the course of the first month or so. Some of the suggestions in post #2 here may be helpful as well.
If the only issue with a mattress is that it is too firm and there are no soft spots or sagging in the mattress then a good quality topper can certainly be an effective way to add some additional softness, “comfort” and pressure relief to your sleeping system but the only way to know for certain whether a specific mattress/topper combination is a good “match” for both of you in terms of comfort, firmness, and PPP is based on your own careful testing or personal experience on the combination. If you can’t test the combination in person then there will always be always some risk and uncertainty involved in adding a topper because the specifics of the mattress itself along with your own body type, sleeping position, and preferences can affect which specific topper would be a suitable choice on any specific mattress and it’s possible that if the mattress/topper combination works well for you then it may be too soft for your wife…
There is more information about choosing a topper and a link to the better online sources I’m aware of in post #2 here and the topper guidelines it links to which along with a conversation with a reliable and knowledgeable supplier (that can provide you with good information about how their toppers compare to each other or to other toppers they are familiar with that are available on the market) can help you use your sleeping experience as a reference point and guideline to help you choose the type, thickness, and firmness for a topper that has the least possible risk and the best chance for success. A good exchange/return policy can also reduce the risk of an online topper purchase so I would make sure you are comfortable with the options you have available after a purchase just in case the topper you choose doesn’t turn out as well as you hoped for.
It’s not unusual at all for a couple to have different needs and preferences and here is more information in the first part of post #2 here about some of the different ways that can be used to accommodate a couple that have very different body types or sleeping styles or different needs and preferences in a mattress.
I’m not sure what you’ve read since you found the site but just in case you haven’t read it yet … the best place to start your research is the mattress shopping tutorial here which includes all the basic information, steps, and guidelines that can help you make the best possible choice … and perhaps more importantly know how and why to avoid the worst ones.
Two of the most important links in the tutorial that I would especially make sure you’ve read are post #2 here which has more about the different ways to choose a suitable mattress (either locally or online) that is the best “match” for you in terms of “comfort”, firmness, and PPP that can help you assess and minimize the risks of making a choice that doesn’t turn out as well as you hoped for and post #13 here which has more about the most important parts of the “value” of a mattress purchase which can help you make more meaningful quality/value comparisons between mattresses in terms of suitability (how well you will sleep), durability (how long you will sleep well), and the overall value of a mattress compared to your other finalists based on all the parts of your personal value equation that are most important to you.
If you are only considering online options then the mattress shopping tutorial includes several links to lists of many of the better online options I’m aware of (in the optional online step) that include many different types and categories of mattresses in a wide range of designs, budgets, firmness levels, and with different return/exchange policies that would be worth considering.
If you are also interested in local options then if you let me know your city or zip code I’d be happy to let you know about the better options or possibilities I’m aware of in your area.
If you slept well on a mattress made by a local manufacturer for 10 years then I would certainly consider buying another mattress from them as well.
Phoenix