My marriage is falling apart

My husband (19) and I (19)had our daughter 4 months ago everything was great until he made friends with this female coworker 2 months ago. Since then he has been distant and fight have been almost every day. We had a huge fight last night where he said he never wanted to be a father and that he couldnt filly commit to our fqmily and that he cant choose between our family and the single party life. Well it seemed we had had worked things out last night, even made love, but this morning he said he still couldnt decide. This led to another fight and now he is deciding tonight whether our not he wants to stay together or split up. I have my daughter and Is bags packed in preparedness for the worst but I dont know what to do I am watching my world crumble around me! help!!