Dreams can often reflect our subconscious thoughts, emotions, and unresolved feelings. Your dream about your ex-girlfriend, family, and the setting of both your hometown and college may symbolize several layers of meaning.

1. Ex-Girlfriend's Presence: Seeing your ex in a family setting could indicate that you are processing your feelings about the relationship. It might suggest a desire for closure or reconciliation with your past. The fact that she joined a Bible study could imply a longing for acceptance and understanding, especially given your family's conservative values.
2. Family Dynamics: Your family's involvement, especially your deceased grandmother, may indicate a connection to your roots and the values instilled in you. It might also reflect anxieties about how your family perceives your identity, particularly in relation to your sexuality and past relationships.
3. Transition Between Locations: The switch from your hometown to college could symbolize your journey of self-discovery and the contrast between your past and present life. It may highlight the tension between who you are now and the expectations placed upon you by your family.
4. Social Interactions: The mingling with people from your college suggests a desire to reconnect with those who understand and accept you more fully. This part of the dream may reflect your need for community and support as you navigate your identity.

Overall, this dream seems to encapsulate your feelings about acceptance, identity, and the complexities of past relationships. It might be helpful to reflect on what emotions this dream stirred within you and how they relate to your current life situation. Consider exploring these feelings further, perhaps through journaling or talking with someone you trust.