It's normal to have sudden waves of sadness and longing for someone you care about, especially if you have a deep emotional connection with them. It's possible that certain triggers or memories are causing you to feel this way. To address these feelings and move forward, I recommend the following steps:

1. **Acknowledge Your Emotions**: Allow yourself to feel the sadness and longing without judgment. It's okay to miss someone and feel emotions deeply.

2. **Identify Triggers**: Try to identify what triggers these feelings. Is it a particular song, place, or memory? Understanding the triggers can help you navigate and cope with these emotions better.

3. **Express Your Feelings**: Consider expressing your feelings through journaling, talking to a friend or therapist, or even writing a letter to the person you miss (you don't necessarily have to send it).

4. **Self-Care**: Take care of yourself during this time. Engage in activities that bring you joy and relaxation, such as exercise, hobbies, or spending time with loved ones.

5. **Reflect and Evaluate**: Reflect on the relationship and the reasons why you miss this person. Are there unresolved issues or unmet needs that are causing these emotions? Use this time to evaluate what you truly want and need in a relationship.

6. **Time and Patience**: Healing takes time, so be patient with yourself. Allow yourself to grieve the loss or absence of the person you miss, and trust that with time, these feelings will lessen.

Remember, it's okay to miss someone, but it's essential to take care of yourself and focus on your own well-being as you navigate these emotions.