Your skin will not make enough protective lipids regardless of whether you use moisturizer or not. With your skin, it's actually better if you use it every day, at least on areas where you get eczema.
Eczema (or Atopic Dermatitis) is an incompletely understood skin disorder, in which the normal skin barrier function (permeability) is compromised, allowing the skin to dry out more than normal skin. The cause of the dryness in AD is thought by some to be a deficiency of a naturally occurring fatty substance in the skin called ceramide. Others believe it's an abnormal or missing protein which causes the skin barrier to be compromised, allowing allergens and irritants to cause immune responses more easily, triggering the itch/chronic inflammation (this might explain the response seen with topical steroids).
Whatever the case may be, moisturizers do provide a barrier of some type to the skin and help to decrease transepidermal water loss; therefore they are highly recommended for AD. Not using moisturizer will leave you open to more problematic eczema. Your skin will not make enough protective lipids regardless of whether you use moisturizer or not. You should use it every day, at least on areas where you get eczema.
Other things which help Atopic Dermatitis involve water temperature when bathing (the cooler, the better), patting your skin dry instead of vigorous rubbing, applying the moisturizer immediately after bathing when your skin has already been moistened by the water, getting a reasonable amount of sun on affected areas, avoiding wool and heavy clothing that might make you sweat, using "gentle" soaps (only soaping up areas that need cleaning), showering briefly twice a day instead of once (applying moisturizer afterwards!) etc.
There are some new ceramide-based moisturizers that have been shown to be helpful in AD. Some are very expensive while others are more reasonably priced. Some dermatologists have recommended TriCeram. You can spot test it (one arm or one affected area) to save money while evaluating how well it works for you.
Determining what kinds of moisturizers work best for you involves trial and error, but whatever works, from petrolatum or Aquaphor, coconut oil (frectionated coconut oil and Johoba oil absorb into the skin a bit better so are less greasy), or another type, don't be hesitant to use it. Your particular skin needs it.
Ceramide-dominant barrier repair lipids alleviate childhood atopic dermatitis: Changes in barrier function provide a sensitive indicator of disease activity
Study Supports Theory That No Single Genetic Defect Explains Atopic Dermatitis
Atopic dermatitis - Mayo Clinic