Shortened version of live, laugh and love, an expression commonly used by middle-aged white women. Li, La,Lo is used by cool moms who drink wine and are under the age of 40, their largest worry in life is their kids wanting to quit the club they put them up too.
"MOM i gotta get to school"
"okay babe, remember to Li,La,Lo"
(used in sarcastic,ironic way)
"Oh my god did you see Mary-anne trying to discipline her child on the playground today!"
*laughs out loud* "all i can say is Li,La,Lo