Experiences of the etheric, the astral and beyond are healthy and should be encouraged. The apparent unknown is always ridiculed by people but 5000 years of human civilisation has not seen the continued experiences of other levels of conciousness or reality stop, of course its real....what nonsense to suggest otherwise.
It is a common truth that what you perceive is based on the induction and translation of frequency, we are capable of perceiving much more than just the physical world. Astral projection is just that, it is projection, you are projecting a resonance of yourself through which your conciousness can remotely experience places outside of your own body. That is not the same as your conciousness leaving your body. You are simply utilising the form of conciousness that exists all around us, that constitutes what we call reality, its what physics calls the zero point field, its what the 18th and 19th century scientists called the ether, the greeks even had a name though it escapes me.
Everything is part of the same field, including us, of course we can perceive other parts of reality, we are simply perceiving an extension of ourselves. To some this will sound like bullocks, hopefully to others it will make sense