Is he ashamed of me?

I am a divorcee w kids, while my bf is a single man. My bf told me his mom doesnt approve of us cause im a divorcee. While some of his friends been telling him he can do better. My bf introduced me to 2 of his friends, but he refuse to let his other friends meet me cause he said they always lecture him about me. Yet, they always invite him to parties and tell hIm to bring me along. But he stop hanging out with them after he dated me. He said the same with his mom, that he doesnt want her to meet me cause she will lecture him. All his other brothers has been married to divorcee, and their mom wasnt against it. And all his friends wants to meet and get to know me. Plus, i notice that when we take breaks, he goes hangout w his friends, and hes still in contact w his mom. He claims he cuts them off because they dont approve of me. So im thinking maybe hes ashamed to be seen with me? Or is he really just trying to stay away from getting lectured? What do you think?