Well, I've already blogged about the Sumerian Inanna, but she's just the first in a long line of goddesses who have LUST and LOVE in their divine portfolio.
In Babylon, she was known as Ishtar. In Canaan, as Astarte (I haven't done the requisite research, but I really wonder if Anat and QDS [the Holy Lady] are not just other names for Astarte in Canaan). She is famous in the Greek-speaking world as Aphrodite, but the Romans called her Venus and by that name she graces the night sky both at its beginning and end. Some of these early figures put war under the aegis of the goddess of love, reminding us of the saying, "All is fair in love and war." Maybe the Greco-Roman mythology makes this same connection by means of the love affair between Venus and Love.
Lesser known figures are Benzaiten (Benten) in Japan and the Aztec Xochiquetzal. I'm surprised that there are not more heterosexual divine couples sharing this domain, such as Rati does with her husband Kama in India.
More common is the male fantasy of divine women fighting over who gets it. In Egypt, Hathor and Bastet cat fight over it. In Scandanavia, it's Frigg and Freyja, and the former gives her name to the sixth day in English's Friday. In Yoruban religion, Oshun gets competition from the Mami Wata.
Turning from real world examples to goddesses in gaming, I was always surprised by how Love got short-shrift in the core D&D pantheon. I think this was redressed in the Forgotten Realms by multiple figures, although, as I've said before, I'm far from an expert in the Forgotten Realms. I was not surprised that Paizo made up for this lack of attention in their world-building. In Pathfinder's Golarion, they follow the trend noted above by splitting the field and giving lust to Calistria and love to Shelyn. (For images, see here and here.)
For the goddess in my own mythopoesis, I like the idea of keeping lust and love together, and adding in luck. This follows the example of Benzaiten, and I think makes sense. Perhaps Lakshmi also comes close to combining Lady Luck and Lady Love. Is there anything that feels more dependent on luck than getting lucky? Or, to put it another way, doesn't everyone want to be lucky in love? I'll keep working on it.