The moon represents our mother - how we perceived her, how she nurtured us and how this relationship still influences our emotional receptivity.
When this luminary is in the 8th house of the chart, which is the area of power and other people's resources, this can indicate a rather unhealthy relationship with the mother.
Your mother might have given a lot to you - however, she will also tend to make you feel guilty for that!
People with moon in the 8th house might experience shame for all the things their mother has sacirficed for them, which makes them feel like they are now in debt to her. This is rather subconscious, though.
They might have the image of their mother saying "I do so much for you, I have given up dreams for you, I give you everything in my power" (depending on the sign the moon is in this could be expressed more self-depricatingly or more angrily)
People with this placement might internalize this voice making them subconsciously think that they are bad for being the reason their mommy had to suffer so much.
This guilt now controls them which consequently gives their mothers a lot of power over them, simply by saying "After all I have done for you, you can't just do this ONE THING for me?"
This same dynamic will also keep on reflecting itself in friendships and relationships.
This can cause someone to become emotionally reserved, in as far as feeling uncomfortable with both giving and receiving nurturing.
"When I care for others too much, I might make them feel in debt to me. When I let others care for me, I will be a burden that sucks away from their life!"
These individuals are really scared of having their emotions (Moon) tied up in this power struggle (8th house) which often keeps them from opening up at all.
They can be secretive and private and really control their emotions - which will only make them more extreme in the end.
This dynamic will ultimately always keep you unfulfilled, because you won't let yourself have your needs met by others, since that makes you feel bad.
You might even deny those needs completely by making yourself believe that you have complete power to provide all emotional support for yourself.
This is not the case, though, I can tell you from personal experience.
You alone will never be able to fill up your own cup.
You will have to get rid of the belief that demanding nurturing from others makes you bad and a drain.
Only when you can truly receive, you can also truly give.