My husbands ex-wife appeals to set aside their ex parte divorce

My husband was granted an ex-parte divorce from his first wife by the sessions court on the basis of cruelty. His ex wife, though aware of the divorce proceedings, refused to participate and refused to show up even after receiving the court summons. I got married to my husband three years ago, after completing the cooling period of 90 days after the divorce decree plus we waited another 38 days more before marrying in the court in the presence of witnesses. Now after 177 days since the divorce decree, his ex-wife has filed a condone delay appeal to set aside the decree and this has been granted by the sessions court. As a woman, I feel my marriage which was conducted following the proper legal procedure is being threatened. Please advice what I should do to save my peaceful marriage? What are my legal options to safe guard my matrimony? Can the court nullify my legal marriage? Many thanks.