This quote suggests that if another woman manages to attract or become involved with your partner, the best revenge is to let her keep him because a real man cannot be stolen. It implies that if your partner is truly committed and loyal, no external influence can take him away from you.
The quote appears to convey the idea that a confident and secure person will not engage in petty actions or seek revenge in such situations. Instead, they trust in the strength of their relationship and the fidelity of their partner. By letting the other woman keep him, it may imply that the relationship was not as strong as perceived, and it's better to move on and find someone better suited.
However, it's crucial to remember that relationships are complex, and no single response is universally applicable. Trust and communication are essential in handling situations involving third parties, and it's vital to address any issues or concerns with your partner honestly and openly. Every individual and relationship is unique, and the best course of action depends on the specific circumstances and the values and needs of the people involved.