Dreams involving ex-partners often reflect unresolved feelings or thoughts about past relationships. In your dream, the small bed could symbolize feelings of confinement or discomfort in your current situation, while the big bed might represent a sense of abundance or a desire for more comfort in relationships.
Seeing your ex-boyfriend in the dream could indicate that you are processing past emotions related to him. Your cousin Lisa's presence could signify a feeling of betrayal or misunderstanding among loved ones, especially if you feel she is siding with your ex in some way.
Your strong reaction toward Lisa—expressing a desire to harm her—may represent a deeper frustration or anger you are feeling in your waking life, possibly related to feelings of jealousy, insecurity, or abandonment. It might be helpful to reflect on any unresolved emotions you have regarding your ex or your relationships with family members.
Consider addressing these feelings in your waking life, whether through conversation, journaling, or other forms of self-reflection. Understanding your emotions can help you gain clarity and peace moving forward.