Dreams involving family dynamics and emotional exchanges can often reflect your subconscious feelings and concerns. In your dream, the gas station symbolizes a transitional space, representing the changes in your relationships, particularly as you navigate the separation from your soon-to-be ex-husband. The act of dropping off the children can signify the ongoing adjustments and the emotional complexities that come with co-parenting.

The presence of both daughters indicates a bond that exists between them, possibly highlighting your concern for their emotional well-being amidst the changes in family structure. Your daughter’s connection with her half-sister and the sadness you felt in the dream may represent your own fears of loss and abandonment not just for yourself, but for the children as well.

This dream could be an expression of your worries about the impact of the separation on your children’s relationships and emotional health. The tears and sadness of the other girl may symbolize feelings of helplessness regarding the situation and a desire to protect the bonds that are important to you.

Consider reflecting on how you can nurture these relationships despite the challenges. Open communication with your ex-husband and finding ways to support your daughters in maintaining their connection might be beneficial. It's essential to address any feelings of sadness or loss you may be experiencing in your waking life, as they could be influencing your dreams.