My fiancé is no longer in love with me..

We've been together about a year and a half.. We've been fighting so much and our fights get really nasty. We've been living in out own apartment for about 3 months and the fights haven't ever been this bad. We're currently trying to work things out but I am so scared that he's going to leave me and I don't know what to do.. I love him so damn much and I really don't want to lose him. What should I do? We used to be the couple everybody was jealous of.. 💔