Astrophil and Stella contains 108 sonnets. In addition, it also includes 11 songs (longer poems that are lighter and more lyrical than the sonnets). The sequence is based on a real-life relationship between Sidney and a woman named Penelope Devereux.
Sidney's relationship with Devereux never did develop into anything permanent. In fact, Devereux married a man named Lord Robert Rich in 1581. And in 1583 Sidney himself married a woman named Frances Walsingham.
However, the student should be aware that the loose events noted in the poems are more fictional than factual. Sidney purposely creates names for his fictional characters. Astrophil is the male lover, the speaker in the poems, who suffers from unrequited love. Stella is the woman that Astrophil adores. The names are symbolic. Stella means star, and Astrophil means a lover of a star. Of course, there is an obvious problem for an earth-bound human who is in love with a star. The star is too distant. The star is unreachable.
Thus, even from Sidney's title, we can deduce that Astrophil will never achieve his goal. He will never win the love of Stella.
On the other hand, students should note that the name Astrophil does contain part of Sidney's own name: Phil is short for Philip. So, the emotions that Astrophil experiences may, in all probability, reflect some of Sidney's own emotions for Penelope Devereux.
According to historical sources, though, the real Penelope Devereux was a much warmer and kinder woman than Stella seems to be. In many of the poems, Stella is icy cold to Astrophil. However, the sonnets also do reflect occasions when Stella does show care and some affection for Astrophil. So, there could be more truth to the sonnets than historians have discovered.