The phrase "when love is a losing bet" metaphorically refers to investing emotionally in a relationship or love that is doomed to fail or not reciprocated. It conveys the experience of continuing to love or hope despite knowing the relationship is a losing or hopeless cause. This idea is often illustrated through the metaphor of gambling or betting on "losing dogs," meaning the speaker knowingly bets on love that will not win or succeed, yet persists because the emotional engagement or feeling is preferred over emptiness or no love at all. It reflects themes of loyalty, sacrifice, addiction to love, and the pain of loving someone who may not return the feeling or where the relationship is essentially toxic or doomed from the start.
In popular media, "When Love Is a Losing Bet" is also the title of a dramatic series about a man who marries for money but ultimately lets go of the woman he loves because he realizes she belongs with someone else; this storyline reflects the theme of love being a losing bet when love is unreciprocated or constrained by circumstance.
Overall, the expression captures the painful yet poignant reality of loving against the odds, knowing the odds are against it but holding on to the hope, emotional connection, or feeling that love brings nonetheless.