I highly recommend seeing a licensed counselor/therapist. If there is no danger of physical harm (i.e. assaultive behavior, sickness induced by depression) then there is hope.
I would do nothing to try and steer her from the JW religion. She will only see that as an attack and an excuse to withdraw from you. Perhaps even secretly hoping you will leave and divorce her.
Rather, be supportive while doing your own thing, but also always willing to do non-religious things together. Work on being the best you as possible. Remember PIES -
Physically attractive
Intellectually attractive
Emotionally attractive
Spiritually attractive
That last one does not mean religion. It means you have a set of morals and ideals you believe in, but also practice.
If your wife feels safe in the fact that you are not doing anything to discourage her from being a JW she cannot use that as an excuse to withdraw from you. Reassure her that you respect her freewill to chose a religion and to practice it. Let her know that you do not want to do anything interfere.
If she wants to attend meetings ask her if she needs a ride. If she wants to attend a regional convention ask her how you can help her attend. Support her decision to be a Witness.
In the end, her own belief system demands she respect you. If you actively support her life and ministry she has no ground to stand on to separate or divorce. That leaves her with these options -
Be in a miserable marriage
Separating or divorcing you, but having to be single or risk being disfellowshipped
Be a happy JW with a happy marriage to a non-believer
Option 1 is directly tied to option 3. If she is making the choice to hamstring the marriage because she doesn't want to be married to a non-believer, let her do the dirty work and have the blood on her hands. Show her you can be happy without being a Witness. Let her learn the hard way that JWs break up happy marriages and families.