For me, the most powerful section of this poem comes at the end of the third section: "Between us is no thought of pain,/Peril, satiety." Knowing the history of the two women/lovers behind the Michael Field name and the society in which they lived, I believe that these two verses could refer to the torment and uneasiness they lived with when they were out in society. The poet feels safe when she is with her lover. Together, they provide a sanctuary for each other which protects them from the homophobia of greater society during their time.
The final four verses also intrigued me: "And if care frets ye come to me/As fresh as nymph from stream or tree,/And with your soft vitality/My weary bosom fill." The fact that the nymph comes from nature (stream or tree) suggests that she is away from society and its artificiality and norms. The nymph (I assume she represents the poet's lover) allows the poet to escape the stress that society causes her on account of her sexual orientation. The poet is thus, for a short time at least, escape into nature with her nymph, where they can practice their love free from the judgment and criticism born from society.