Watching porn while giving oral sex

Okay so I can be very sensitive at times. I really love my SO and i love making him feel good but I feel shitty because hes on his phone when i give him oral. Not only is being on the phone rude, but he watches porn while I do it, i found out and he trys to hide it from me, like he'll lock his phone real quick. Like why does he do it? Am I not good enough that he needs to watch other people fucking while i'm trying to please him, I don't like it at all it makes me feel like I'm not good enough and it hurts, Any time i bring it up he's defensive. Idk what to do.