This poor bee died on the milkweed flower. Its feet were caught in the flowers and it was unable to pull itself out (a common problem for insects feeding on milkweed). I managed to remove it to check for the pollen packs on the feet (those yellow packets) and at the same time I saw there were numerous small flies on the body. Bug Guide thinks they may be in the Genus Desmometopa, the Freeloader Flies, and they note that:
"Females are kleptoparasitic and are especially attracted to predatory insects or spiders feeding on honeybees". So there may have been something else feeding on the bee that I didn't notice and scared off when I picked it up.

Those insects who do pull free from the milkweed plant (which is most of them)help carry on the process of pollination: http://www.pbase.com/laroseforest/image/106006341