So - nothing you do matters to anyone else.

Thats pretty much true for everyone, unless they make some kind of contract with someone else, like by getting a job, or having a baby, whatever.

But otherwise, it's the way things are. All your physical needs are being taken care of by your husband, so you dont have to provide for yourself there. So its pretty much up to you to look at Maslows hierarchy of needs and pick something. You have a choice. You have freedom. You are of the physical age where you should start developing a feeling of generativity - wanting to contribute to the next generation. Maybe there will be something there.