1. If the married solemnized in Indian as per Indian matrimonial laws, the divorce decree obtained through foreign court can be invalid on the following grounds:
1. The grounds for the marriage are not available in Indian matrimonial laws. For example "No fault divorce" is not a valid ground. So, such decree obtained in foreign land is not recognized by Indian Courts and the estranged spouse can challenge such decree in Indian courts.
2. If the respondent, here the wife, is not in a position to contest the case on any one of the situations, like financial incapacity to stay there in foreign land, engage a counsel being very costly in developed nations etc.
Indian matrimonial laws and also women protection laws are available to you. In addition to this, as he is mud slinging business about character, you can file criminal defamation case. Consult a local advocate and file suitable cases. If he wants to stick up there and does not want to venture to come here, at present, Indian laws cannot be enforced to bring him back, as they lack teeth. Any attempt to get orders for non-renewal of his passport once it expires further exacerbates the already gloomy situation. In a nutshell, if he gets divorce decree without your consent in foreign land, then also he cannot remarry on Indian soil and if he does so, it becomes bigamy which attracts very severe punishment.