What a blow for Moses!
Parashat Chukat includes the deaths of his both of his siblings - Aaron and Miriam. After Miriam dies, the wells of water that accompanied the Israelites during their desert wanderings ceased and the people complained bitterly. In reaction, Moses struck a rock in order to emit water for the thirsty Israelites rather than follow the Divine command to speak to it. As a consequence, he was told he would not be allowed to enter the Promised Land. His punishment was harsh. What was Moses' mistake? Commentators offer various opinions: Moses lost control of his temper; he was supposed to speak to the rock, but instead struck it; he blamed the people for complaining and then took credit for bringing water, credit that should have been attributed to its Source, the Holy One. There is no one 'right' explanation.
Parashat Chukat are laws for the strange ritual of purification with the ashes of a Red Heifer and the beginnings of the Israelite conquest of Canaan.
What can we learn? The key, I think, is in the title of the parasha. Most of the laws in Judaism are rational and understandable. A very few are in the category of chukah, statutes commanded by God with no rationale or reason given.
Parashat Chukat, Moses undergoes great personal trial and adversity: family deaths, severe punishment for something that seems minor, learning that he will not be allowed to accomplish his life's goal of bringing the Jewish people whom he has led through trial and tribulation into the Land of Israel, with no rationale given. The Torah does not give us any insight into Moses' reactions; the entire episode defies explanation.
What we know is what Moses did - he continued to lead our people with determination. Even upon learning his fate, he did not give up.
When we face adversity and challenges in our lives for which there is no explanation, we can give up or we can make the choice Moses made to carry on, stay the course, provide support and love to others and be a blessing.