He has a wall up??

My bf has an emotional wall up and I don’t know how to break it. He cuddles with me and kisses me and we laugh, but he doesn’t get very engaged in my conversations. Like when he’ll talk about something that happened with him, he could go on for hours, but when it’s me talking about something, it’s usually short responses. He doesn’t tell me how he feels. He said it’ll take time for the walls to come down, but I’m not convinced. If he loves me, why are they even up? What can I do? I always question if i matter because of this.