I have trouble with the whole "those darn millennials" thing. I am constantly meeting really impressive young people who have started their own businesses and non-profits, and none of them seem especially entitled. As thomas already pointed out, it really comes down to the parenting, and there are bad parents in every generation.
Perhaps with the circles you move in, you would only meet certain types of Millennials? There are a lot of good ones out there, and we have a lot of good traits. We're the most tech savvy, we're the most global, and we're the most open generation the US has ever produced. Combine that with motivation and discipline, you have some people who will really contribute to society in a variety of ways (as some are already).
It just seems so many others are willing to impute the responsibility of failures on everything but themselves. As Thomas says, it's mostly about the parents, directly and indirectly (the way in which Baby Boomer parents have influenced the school system...some places don't even give out F's any more). I wonder what sort of people Gen X will produce. And come 2030, we'll see what kind of parents we make.
But regardless of the cause, Millennials like the one the OP is having to deal with need to look at their approach to work and life, accept that it's not the best one, and change it. It might be her parents' fault she is the way she is, but it's now her responsibility to change it.
Pulling this thread off topic, but I would love to hear Holdfast's take on this.