I looked around but did not see this answered.

If I have endless greed to where I can not lose items, What happens when I am reduced to 0 sanity or stamina? So i guess the question is: Is discard the same as lose?

Endless Greed won't allow you to trade money, not items. But yes, if you were arrested, you would not have to lose the money unless you choose to.

Jealous Guardian is the same thing with items. If you go unconscious or insane, you do not have to lose the items if you don't wish to. Sometimes Corruption cards can be a good thing.