You would have to file for securing custody of all the children based on evidences in the court pleading that she is not competent to maintain the welfare of children as has been decide in various Supreme Court judgments.
As far as not paying maintenance to your wife is concerned, you would have to prove that she has illicit relationship with other man, for which I understand you are having adequate proof as mentioned above. Also, the fact if she is a working lady is important to waive off maintenance.
thanks.
