Most people want to be wanted and to feel valued and valuable. Sometimes people mistake being needed for being wanted. Did your spouse have a person in their background who was dependent on them? Perhaps his mother and/or father? Was his parents' dynamic one of co-dependency? He/You maybe interested in reading Getting the Love you Want by Harville Hendrix.
It reminds me of a story I read in Too Good to Leave, Too Bad to Stay (good book), I think. Maybe it was in Feel the Fear...and Do It Anyway. It's about a woman who was married and stayed at home for a while but then went back to school. Her husband had been supportive of her going back to school and referred to her as "his little student" or something else seemingly innocuous but really not good. After school, she decided to get back to the work force and maybe start her own business and her husband completely changed. He felt threatened by the new force growing within her and wanted her to stay in that role he was used to.
If if you have a conscious relationship with a conscious person, talk to him about it. Perhaps he does feel valued and important if you need him. Perhaps that's not such a great thing to base his sense of value around.
Maybe this will help?
Codependency & Recovery from codependent relationships
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