Demas (2 Timothy 4:10)

In 2 Timothy 4:10, Paul tells Timothy that Demas forsook him because Demas "loved the present age." Just exactly what this phrase means has been hotly debated. Gordon Fee writes that apostasy is signified by the phrase AGAPHSAS TON NUN AIWNA (1 & 2 Timothy, Titus [New International Biblical Commentary], Page 299).

Yet Thomas D. Lea avers: "Paul's words [in 2 Tim. 4:10] did not picture him [Demas] as an utter apostate but reflected disappointment at his self-interest" (1 & 2 Timothy, Titus [New American Commentary], Page 252).

My question: does the use of AGAPH here or anything contained in the syntax of this Pauline account suggest that Demas was an apostate? Or could it be that he simply left off sharing in Paul's ministry, which shows something about his spiritual state, but does not mean he became an apostate? Lastly, if Demas was "saved" and did in fact defect from the apostle and (more importantly) the Lord Jesus Christ--it would seem that a genuine Christian can apostatize after experiencing God's unparalleled XARIS.