What can I do to save my marriage from his friends?

I’ve been married ten days, we got married at the court house without telling anyone because we were in love and so happy. All his friends are happy for us, both our families are happy. But he has an ex girlfriend who is upset because they broke up three years ago and all that time she was holding feelings for him but never showed it. When she heard we got married, she had a big blow out fight with me and him and her mom was there too backing her up. They said he should be with her and I don’t love him like she does. But they don’t really know me! The mother wants to see my husband and her daughter back together and my husband has no interest in getting back with the daughter, but he wants to stay friends with the mother and the rest of the family. He told me he was going over there to try to stick up for us and our happiness, he kissed me so sweet and promised me no matter what we would be okay. He came home three hours later and wanted a divorce!! He said he is just too young, we moved to fast, he doesn’t know me that well, and he wants out. He says he still does not want this other girl, but that family is so important to him he can’t give them up as friends, which I was asking him to do. I can’t go over there, they hate me and won’t let me in, and while he is over there all they do is tell him lies about things I never said, and they convince him I will cheat on him and leave him and I don’t love him. He visits them twice a week or more and they take money from him and use him and lie to him. But he trusts them more than me. He’s known me for four months, them three years. What am I to do? I convinced him I love him with my whole heart and want him for the rest of my life, and he said we’d give it a little more time to see how it works out. But all they do is sabatoge things. And he keeps going over there and he is blind to their manipulation. He can’t see their motives at all. He thinks they are true friends. They do not care about his happiness, only getting him away from me and back with her. He is blind to all this. How can I keep my husband and let him keep his “friends”?? Help!! and thank you. Michele.