While Kortney did seem to have started out as looking like someone so stupid that she needed a spotter to breathe, it soon turned out that she was simply something of a parasite trading on the same sort of idiot generosity that Elly only seems to display to people who are actively trying to take advantage of her. Fortunately for Elly, someone with the will to dare and to do saw right through the sob story and confronted the jerk. Despite the hindrance of having to wait for Elly to leave town and thus give Kortney time to come up with a cover story good enough to fool people, Moira did save Elly from her own stupidity and explain to her that she'd been lied to for quite a bit of time. Elly's reaction was one of disbelief and to assume that Kortney was simply a troubled child who needed a hug and stuff when it was obvious as all Hell that she took someone for a ride with her own permission because she wanted to feel like a mentor guiding someone instead of an employer looking out for the bottom line.
This means that Elly is as honest as they come about what she wants out of life and what she expects of the people around her but she still got played for a sucker because asking the right questions makes her feel bad.