Serious relationship

My boyfriend and I bought a house together. We are losing our touch because I feel like moving in and buying a house is a serious thing in an relationship. He thinks to believe the more serious I am with him the more it’s going to push him away. He just wants to me to be his best friend and have a blast with him, like we did in the beginning. So i guess I’m just confused on what to think, because he says we both aren’t going anywhere we bought this house. He goes I’m a simple man, be my best friend, love me, don’t make everything so serious all the time. Thoughts?