Solitariness
/ˈsɑːləterinəs/
Definition 1 of 2
Pro Tip 1/3Emotional Weight
Solitariness often carries a sense of sadness or contemplation. 
In the silence of the night, her solitariness was palpable.
Pro Tip 2/3Not Always Negative
Solitariness can also suggest peace and self-sufficiency, not just loneliness. 
He found solitariness in the mountains, a welcome respite from the city.
Pro Tip 3/3Literary Use
Often found in literature to describe a character's isolation. 
The protagonist's solitariness was a recurring theme in the novel.