Vivian: You don't seem to be overreacting. It isn't like this is a Playboy he looks at occasionally. This has reached the point that it's becoming a major part of his life and is impacting the family's finances. That's going past casual use. It sounds like he may have crossed the line into compulsive behavior.
It sounds like you may need more help than you can get on a Forum. Obviously, I don't know your religious background, but here is a site that helps link people in these situations to resources. I think the lady's account will strike a chord with you.
Dealing With Internet Pornography AddictionFYI, this is a growing problem. The number one reason that pastors seek mental-health services is compulsive use of internet pornography. The fact that he got angry when you mentioned it is a sign that he's developing a problem with it.
The majority of people who view pornography do so responsibly and occasionally. However, like alcohol or gambling, some will develop a problem with it. I don't think you're just blowing things out of proportion.
Best wishes in dealing with this situation. There is no easy answer.