I did everything that she requested of me
Counter intuitive, but you need to stop this immediately. You are not responsible for her happiness and catering to her every whim will decrease her attraction for you instead of your intended reasons for "making her happy."
From this point on, keep your mouth shut, and start doing things for yourself, that make you happy. No amount of you being nice to her, begging her, whining about how bad you feel will get her to change.
Look up and implement the healing heart - the 180. Then download and read the married man sex life primer and the mindful attraction plan by athol kay, and last but not least "no more mr nice guy" by dr robert glover.
Next up, consult a lawyer about your options for separation/divorce and get papers ready for signature.
Rule out any type of medical conditions (change in birth control/medications/whatever) and also rule out any outside influences, such as another guy. (disclaimer: not saying your wife is having an affair, but you have to rule this out completely in order to now what you are dealing with beside the obvious.) Her actions warrant a look into her activities outside the marriage.
Keep working out, keep improving your appearance, keep improving your social and intellectual self. Ignore anything negative she has to say about you.
Work to separate your finances from hers. Put in money to cover what bills you need to take care of, but start putting money aside for you that she cannot access. Stop paying/buying anything for her. Example, if she wants to go to dinner, she can pay. If she wants new clothes or items outside the household expenses, she can pay for them out of her pay check.
If she is not contributing to the household expenses, then she needs to start. Lay down that in order to meet monthly obligations, she is expected to contribute x dollars. Let her bitch, but stay firm that you expect her to contribute to your SHARED expenses.
Once you have your wits about you and an exit plan in place, i.e. divorce/separation papers, money in the bank, either another place for you or her (if you own a house, then do not leave the residence) but have a place you or she can crash for a few days...
sit her down and give her two options:
A - straiten her shit out, go to marriage counseling, actively work on the marriage, cut her unhappy bullshit and/or whatever you expect for her....
or
B - divorce and hand her the papers and either leave or pack her bags and have her picked up to be taken to prearranged destination (even if it is a hotel room paid for a few days.)
This is the only way you can save this marriage. It may be too late and you may feel this is too much effort/time but what the hell, at least give her one last try for her to straighten out her shit to make this marriage work for the both of you.
Good luck.