1. The state of being solitary or remote from others; seclusion
[From the Latin word solitudo, which comes from the Latin word -- you guessed it -- solus, meaning "alone"] - Funk & Wagnalls Canadian College Dictionary
The word "solitude" turns things upside down from the often negative connotation of being alone. Solitude is desired and sought by spiritual seekers and stressed out citizens. It implies rest, renewal, refreshment. Solitude often brings connection to spirit and nature -- all so contrary to many people's perception of being alone or solitary.
The words "solitude" and "alone" are called doublets because they came from the same original word (solus), but they entered the language through different routes. Another example of a doublet pair are the words "royal" and "regal."
So "alone" and "solitude" have the same origin and the same basic meaning but such different emotional definitions! And just as the use of a word can change over time in a culture, it can change over time in your own mind.
Allow yourself to seek solitude, to be alone, to enjoy solitary pursuits. What a treat these can be!