Now that Tristan has been rediscovered, maybe it's time for his fabled lover in the Arthurian romances and Wagnerian opera, a beautiful Irish princess, to be brought back into the light as well.
This would make an artistic and romantic choice, as the medieval heroine is seen as a symbol of undying--if unhappy--love.
In Marilyn French's novel The Women's Room, the character Isolde is nicknamed Iso. Isolde is currently a Top 500 name in the Netherlands.
Variations include Iseult, Isolt, Isoud, Isolda and Yseult.