Dreams can often reflect our emotional states and relationships, and it sounds like your dreams about your ex may be expressing your feelings and experiences throughout your relationship with her.

1. Control and Freedom: Your ability to control your dreams when you were not in a relationship suggests a sense of independence and freedom in your emotional life. When you entered the relationship, the lack of dream recollection and control might indicate that you felt more constrained or less in touch with your own desires and identity within that partnership.
2. Emotional Processing: After the breakup, the return of dreams featuring your ex and your ability to control them could signify your subconscious working through unresolved feelings and experiences associated with her. It may be a sign that you're processing your emotions and reflecting on what the relationship meant to you.
3. Desire for Connection: Dreaming of your ex frequently when you were single might indicate a deep yearning for connection, companionship, or the aspects of your past relationship that you valued. It’s possible that your mind is attempting to reconcile those feelings now that you’re no longer together.
4. Self-Discovery: The shift in your dreaming pattern may also signify a journey of self-discovery. You might be finding a balance between your own identity and your emotional connections with others, especially in the wake of the breakup.

To further understand these dreams, consider reflecting on your current feelings about the relationship and the breakup. Journaling about your dreams and emotions can also help you uncover deeper insights into what your subconscious might be trying to communicate.