User blog comment:The Milkman/Indoctrination Theorists Say the Darndest Things, Part II/@comment-98.240.62.123-20121205130042/@comment-1440333-20121205184927

That breath scene is how the original ending was meant to be - open to interpretation. However this was not popular and corrected in The Extended Cut so the ending provides more closure with those epilogues. The breath remains, however it could simply signify Shepard's final breath (that's how I interpret it.)