I'm not sure how exactly, Lex. But probably the very first step is for you to stop defining your own life in terms of being a provider for your wife. You have to get to a place where you feel you want to be a partner, not a parent figure.
I really do think that the more she sees you as a Daddy figure, the less she'll be interested in you sexually. At least in a healthy sexual way.
And, conversely, healthy sexual dynamic can only come around if she sees you as a partner; and she herself feels like an empowered woman.
You've talked primarily about your wife in terms of sex. Other than sex, what do you like about her? What do you find interesting about her? What do you respect in her?
Me: 50, MLC/WW 45 Young kids Nov 2015: BD1 Apr 2016: BD2 Jan 2017: W filed Feb 2017: D final