Your concerns are understandable, especially when it comes to communication patterns in a relationship. It's important to consider several factors and approach the situation thoughtfully.

1. **Work Schedule Considerations:**
- Working a night shift can be quite demanding, both physically and mentally. It's possible his sleep schedule conflicts with your usual communication hours.
- Night shift work can lead to irregular sleep patterns, fatigue, and less time for social interactions.

2. **Patterns and Frequency:**
- Reflect on whether this communication pattern is a recent development or has been consistent throughout your relationship.
- If it's a recent change, it may be worth exploring if there's an underlying reason such as increased work stress or personal issues.

3. **Quality vs. Quantity:**
- While frequency of communication is important, the quality of interaction matters as well. Is he engaging and attentive when you do communicate?

4. **Expressing Your Needs:**
- Have an honest and open conversation with him about how you feel. Use "I" statements to express your feelings without sounding accusatory, e.g., "I feel concerned when we don't communicate as often. Can we find a way to talk more regularly?"
- Discuss and agree on how you both can balance his work commitments with your relationship needs.

5. **Mutual Understanding and Compromise:**
- Find a middle ground that works for both of you. Perhaps you can schedule regular times to talk, even if briefly, that align with his waking hours.
- Consider other forms of communication that might be more convenient for him, such as voice messages or video chats.

6. **Signs to Watch For:**
- If his behavior seems consistently indifferent or evasive, it might be worth considering if there are other underlying issues in the relationship.
- Watch for changes in affection, attentiveness when you are together, and his willingness to discuss and address concerns.

7. **Self-Care:**
- Make sure you are taking care of your own emotional well-being. Engage in activities you enjoy and maintain a support system of friends and family.

In summary, while night shift work can certainly affect communication, it's essential to ensure that your emotional needs are met too. Open dialogue and mutual understanding are key in navigating this issue.