Sentence:  This is fully and quickly intelligible, but what it says is that the process of turning out to be a friend began, not with a set of properties that inconclusively indicated <WSD>friendhood</WSD>, but with a set that in fact inconclusively indicated unfriendliness. 
Meaning of the word marked with <WSD> tags:  The state, quality, or condition of being a friend or friends.