I am one of those cases where I can smell myself and I'm grateful at least for that small thing, but it's still not very reliable.
Your odor will almost always be more noticeable to others, but you don't know by how much. At times I'll feel like I don't smell that bad, yet if I go out of the room and come back to where I stood for a while, the odor in the area strikes me.
I guess you can only be confident if you suddenly can't smell it at all where you previously could. In my case, I had several things that I thought were reducing the smell, only to later find out that they weren't making as big of a difference as I had thought.