Is my Boyfriend a Momma's boy?

We've been in a serious relationship for about 15 months. He's never had a serious relationship before myself. We live together (We rent the house off his parents) He has a lovely family, I really do enjoy their company, and they are kind to me and I'm grateful for that. However, he gossips to his Mother quite a bit. Other family members. Me. Sometimes he tells and invites me into the conversation. I did not. I don't like gossiping. I gently said to him, gossiping can be a form of bullying, you're better than that behaviour. He got defensive and started saying its non of my business, ''its MY family.'' But previous to that. He always said I'm apart of the family and his family love and welcome me. A few months ago, I told my Boyfriend the most personal and intimate thing about me. He told his Mother. In his words 'Just making conversation. Because I wanted too'. Ee had a miscarriage. I was in a bad way in the hospital. I understand he needed to tell work he will be absent for a few days. But he was quick to tell his Mother and his Mother basically said ''She's probably just having a period.'' I needed him that night. He kept going outside to speak to her.
These are just a few examples. Examples that have been hurting me the most for a while. He does see his family a lot. They live up the street. I'm glad he has a relationship with them. Is this going to get worse? Am I with a man that is still being breastfed by his Mother? Will he ever cut the apron strings? Or do I need to deal with my feelings and get over it? I'm not trying to get in the way or take anyone's place. I let him have his days with his family without me all the time. What do you all suggest?

We've been in a serious relationship for about 15 months. He's never had a serious relationship before myself. We live together (We rent the house off his parents) He has a lovely family, I really do enjoy their company, and they are kind to me and I'm grateful for that. However, he gossips to his Mother quite a bit. Other family members. Me. Sometimes he tells and invites me into the conversation. I did not. I don't like gossiping. I gently said to him, gossiping can be a form of bullying, you're better than that behaviour. He got defensive and started saying its non of my business, ''its MY family.'' But previous to that. He always said I'm apart of the family and his family love and welcome me. A few months ago, I told my Boyfriend the most personal and intimate thing about me. He told his Mother. In his words 'Just making conversation. Because I wanted too'. Ee had a miscarriage. I was in a bad way in the hospital. I understand he needed to tell work he will be absent for a few days. But he was quick to tell his Mother and his Mother basically said ''She's probably just having a period.'' I needed him that night. He kept going outside to speak to her.
These are just a few examples. Examples that have been hurting me the most for a while. He does see his family a lot. They live up the street. I'm glad he has a relationship with them. Is this going to get worse? Am I with a man that is still being breastfed by his Mother? Will he ever cut the apron strings? Or do I need to deal with my feelings and get over it? I'm not trying to get in the way or take anyone's place. I let him have his days with his family without me all the time. What do you all suggest?