Fiance said I'm 'replaceable', what should I do?!

My fiancé said I'm replaceable. What should I do now? I, 26 female, met my now fiancé, 27 male, two years ago, and we have been engaged for a year. Compared to my last boyfriend, who was abusive verbally and physically, he is generally a breath of fresh air. He's supportive and is very loving. He's the first person who ever truly loved me, since my parents were abusive as well. Over the past few months though, we've been arguing more. He wants me to quit my job once we have kids so I can homeschool them, but I'm not ready for kids and prefer they go to school. He got more upset with each argument and said I'm depriving him of kids. When I finally suggested that maybe we should take a week apart from each other to cool off, he said that I can easily be replaced at any time and that I'm not special. I feel deeply hurt right now. He was amazing before and that's the real him I saw, but lately he did seem to be depressed from work. It's not an abusive situation as he wouldn't hit me. I want him to get back to his good old self. How do I get him to fix the issue and be apologetic for what he said?