You're boyfriend is addicted to porn, simple as that. He needs to stop watching that **** for like a month and rewire his brain. His brain is wired to think porn is part of sex. Rewire it so porn is left out and so he seeks out the real life physical stuff.
Hi.
I can't answer questions about your boyfriend because I don't know him. If you want answers, you need to have a conversation with him. It seems as though he's given you an explanation, but it sounds as though you don't believe him. This is something for you to explore together in an honest discussion.
I can tell you that many men--and women--find that erotica is a helpful tool for arousal, especially for those that need something to short-circuit any inhibitory messages left over from childhood (i.e., sex is bad and wrong, etc.).
I'm not sure what you mean by your last sentence in which you ask if this is just an "excuse." Do you mean that you think he isn't really turned on to you? If so, on what do you base this? Again, you need to explore this with him.
One idea I have for you besides talking honestly and openly is to perhaps join him in watching something sexy. This could be a shared activity, from which you both might benefit. On the other hand, if you're uncomfortable with the idea of him watching sex, you need to explore your discomfort and share your feelings with him so the two of you can work out what's best for your relationship. Best of luck to you. Dr. J