This word seems to be the antithesis of the phrase "The Life of Riley," but definition 2 does describe the life of Chester A. Riley, Sr, although not that of the actor best known for portraying him.The American Heritage® Dictionary of the English Language: Fourth Edition. 2000.
riley
SYLLABICATION: rile·y
PRONUNCIATION: rī'lē
ADJECTIVE: 1. Stirred up emotionally; upset. 2. Roiled; turbid.
Although no etymology is given in the AHD entry, I suspect it is related to rile, which is a variant of roil, which is said to have an unknown origin by the AHD.
However, the Online Etymology Dictionary says that rile is:
and that roil is1825, Amer.Eng. spelling alteration to reflect a dialectal pronunciation of roil (q.v.); cf. heist from hoist.
1590, probably from M.Fr. rouiller "to rust, make muddy," from O.Fr. rouil "mud, rust," from V.L. *robicula, from L. robigo "rust" (see robust). M.E. roil meant "to roam or rove about."