My friend has a funeral and can't attend the wedding. How should I reply to this message?

"I understand your situation very well. At this special moment, family funeral is undoubtedly more important. Please rest assured that we fully understand and support your decision. If necessary, we are always here. I hope you can stay strong in this difficult period. I look forward to hearing more details from you when we meet next time. I once again regret your absence and express my deep sympathy for the grief of you and your family. "

This reply is full of understanding and sympathy, but it also expresses support and concern, which is suitable for comforting friends in difficult times.