This saying means that one is in a hopeless situation, much like someone who marries an old woman and has to endure the tough conditions that come with it. It emphasizes the importance of respecting one’s commitment and enduring without hope for better rewards or pleasant moments. In other words, one might face continuous hardships while fulfilling one’s duties or commitments, even if the conditions are tough or the gains minimal. The equivalent saying in English could be ‘No pain, no gain’.