Since your contact is limited, maybe start with some physical changes that will catch her eye right away. New haircut, dressing one step sharper than normal, getting in super physical shape, etc...
One thing you don't want to do is verbally broadcast your changes or ability to change. "Hey W, look at me, I'm changing". Actions speak much louder than words, and the consistency of those actions is what will really have her believing you have/are changed/changing.
Don't worry if she doesn't say anything about noticing your changes. You need to change your strategy though if you get negative feedback from her 'cause what you're doing is most likely having a negative effect.
If it's good for you in a positive way, and helps you become a better person, then keep doing those things. How you're feeling about yourself can sometimes be as or more effective than how she presently feels about you. Feelings change, and rather quickly at times.
Read about Divorce Busting« Telephone Coaching here!