Regarding legal action on separation

Sir, i have 2 son's one of age 6 and another of age 1.3 months , i was in abroad and during my second pregnancy. my in-laws stayed with me for 3 months to take care of my first kid, once they pich in they started lots of problem stating bad about me to my son and husband. And my husband started listening his parents and fighting started between us, after my delivery my parents visited to take care of me, and my husband assassinated my character stating these kids born for some other why should I take care of them , as he wants live with his ex girlfriend. i came to India and i was not having phone calls after then with any of his family members, suddenly now my in laws started that they want to meet and they are ready to take legal separation. Their moto to get money from me and to seperate my kids from me, i have job here and taking care of my kids with help of my parents , I don't want to show my kids to them as well as I don't want the guy whom I got married to see my kids , as he was stating that they are not his kids. I don't have evidences as everything happened in short span of time . he drinks everyday.pleas advice