To me solitude is one’s own absolute being. When in complete and total solitude, when no thoughts cloud your self, you are an absorbed being of everything you have learned, will learn and know at this exact moment. It is when we are out of solitude that we become jaded by expectations set forth by other people as well as ourselves. Outside of this solitude, we are merely humans interacting with other humans and nature, wearing different masks to fit different circumstances. When you are in solitude, you are in a spiritual setting, aside from religious connotations or assumptions. There is no religion in this spirituality for religion fits within the realms of mask wearing and jadedness.
You can use this experiencing solitude as a way to subconsciously gather your thoughts and emotions to be interpreted as only your own mind can handle. It is in this state that you are completely and utterly true to your inner and outer selves and thus you can gain impeccable wisdom and enlightenment.
Solitude is meant for relaxation of self, body and mind. For those who feel overwhelmed and anxious is only because they are over analyzing and over thinking the purpose of this act and therefore can not differentiate between the conscious thought and the subconscious mind. Anxiety is the product of a metaphorical struggle between ego and self in which the conscious mind is fighting to relinquish control. It is when you can truly learn to let go and trust yourself, that you can step foot on the path to enlightenment.