He cheated our entire marriage and wants to restart

My husband and I have been married for four years and together for 6. Today he came to me bawling and told me that for our entire relationship, he slept with so many women. He told me al the details, told me when, who. And said that once I got pregnant and we had our daughter his perspective on life had changed. He said he understood if I wanted to leave him, but he told me because he wanted to restart. He told me he has no real excuse except he was 18, immature, and stupid. and never wanted to do it again. Can our marriage be saved. Would I be stupid for staying with him? I’m just so numb right now. Our marriage was bad when he cheated, I’m not denying that. We got married at 18 and we’re both incredibly immature and didn’t know how to communicate. But we decided to fix our marriage and he said this is part of it, which a why he told me... 😞 I’m just not even sure what to think, especially because there is a child involved now.