All anguish is caused by a longing for the past or by worries for the future. Everything is limited by time besides Torah which transcends time. By holding onto the Torah and grabbing the opportunities of every moment, we can save ourselves from anguish. The moon teaches us that anything we lose will be returned to us at the end of time. The celebration of Tu b’Shvat is over a tree which continues to flourish even after its fruit is eaten.