We know that Luna is seen as someone "special" or unusual, according to Skylar and based on what Luna says about herself. I seem to remember she is described as superstitious to the point that it both shapes and restricts how she organizes her daily life, for instance she avoids doing certain things, like going home on full moon nights.
It’s suggested that she might have, or at least believe she has, some kind of gift or ability, perhaps something similar to a psychic or a medium. I assume she sees this both as something positive and as something difficult to carry. Her daughter Skylar seems to share a few of her habits or at least an interest in the supernatural, the mystical, or the spiritual.
As for why Luna hasn’t made progress socially or professionally, I have no idea. Maybe her unusual abilities or beliefs are also a burden, something that affects her both mentally and socially. I suspect that the weight of it all prevents her from leading a serene and fulfilling life.
Or maybe she simply does not want a different life. It is entirely possible that Luna prefers a simpler and more reassuring existence, something more familiar and easier to handle in her own way. Or perhaps it is a mix of both. We will certainly learn more later about the reasons behind her personality and the life she leads in '99 and '19 respectively.