Wife not coming back home and not even legalizing the divorce

I got married in 203. We led happy conjugal life. Bt in the year 2013 my wife left me. There was no disturbence in our conjugal life. Though we have gulf of difference as to age. She is 21 & i 48. I am a diabatic patient. Naturally thrre was some sextual problem. Bt on this issue there was no misunderstanding. In the yar suddenly he left me & started to stay with her parents. I number of time went their place to bring her back bt her family showed less intererst. Later they informed local club & in presence of club secretary & a local law yar an agreement was done with noterry regarding divorce. On that agreement it was stated clearly that later it will be legalised bt now they are not interested. I told her either come back or do it legalise. I am a private tutor. My mother is old & infirm. There is none to look after her except me. What can i do?