Wife is leaving me :(

I've been with my wife now for over 6 years.  We have 2 boys, aged 2 and 5.  When we first met, it was great.  We had lots of time to give towards each other and we loved each other very much.  Over a month ago, my wife told me she is leaving me because of the way things had been for the last 5 years, the way I have been.  This was a slap in the face for me and triggered something in me to start putting things together from my past.  I went to see my doctor and I am now in the process of testing for ADD.  The signs are all there and I admitting that there is something wrong with me.  I have tried to see councilors, couples therapy and other forms of help but nothing stuck, nothing seem to help me, I would never follow through.  I am now in the process of bettering myself and I feel like my wife has abandoned me.  I believe that a family should stick together and try to fix things, especially when the other partner is sick.  She has said that she has gone through too much and can't go on.  I asked her if I get diagnosed with ADD, will that change anything and she said no.  Like I said, I feel completely abandoned from my wife.  She has lost faith in me and this makes me very sad.  I've been told to just let her go and to concentrate on changing my environment, changing my ways, getting better and then just seeing how things happen.  This is not easy.  She is my wife, I need her to help me through this!