Porn. Does my boyfriend have a problem with it or do I?

I've been living with my boyfriend of two years for a year now. We are very happy except I am getting extremely annoyed with what I think is an abnormal porn habit. He looks at pictures and downloads them for about a half hour every other day. Then occasionally he sneaks peeks in while I'm in the shower, making dinner ect. He thinks I can't tell, but the computer screen is always changed or he leaves obvious tracks.

We've gotten into numerous fights about it--mainly because I feel I can't walk around my own house without walking in on him looking (he doesn't masturbate to it at the desk).

I'm upset because I feel like he can't control himself, which I feel is a weakness. Also, just get a little jealous that other "women" are turning him on. I feel like I'm not enough.

He gets very defensive when I bring it up and claims it's normal and something he's done for years. I