It is difficult not to compare this card to the 2 of Cups, as that too is about the coming together of two individuals in a state of union. The Lovers however, is, as its title suggests, a card of a more primal ‘sexual nature’ – lust to initiate procreation. Whereas the 2 of Cups is higher love.
The card was originally about choice, perhaps between two options, or people. There is also the idea of temptation associated with this card.
Insiders Tarot Tip: If the question is about an issue not about relationships, the Lovers card (as suggested by the Hermetic Order of the Golden Dawn in the 19th century) represents intuition. It is the inner knowing, the sudden flash of insight that must be trusted in making a choice – not reason or common-sense.