I see dead people

More often than I'd like, I experience death at work. It is usually a very peaceful event and a somber event. I have seen and taken care of these people for months and then one day, its over and they are gone. Oddly, I have no issue with the dead in this case. I wil stay with them when i can and hold their hands as they take their last breath. And when they are gone, I can be close to them. Why can't i go up to a casket?