Many people fell like that they do not have the right to complain to God. That complaining to God is wrong and shows a lack of faith. I think it is ok to complain, even to God. I was driving in to work today and I heard a clip of a Pastor saying how we should be happy, and thank God for our blessings even during the bad times. He made the point by talking about how David had a hard time a lot in his life. His King that he had only ever been loyal to, wanted to kill him. He had to live out in the wilderness for years, and run from the King just to stay alive. The pastor quoted a passage from psalms that praised God and thanked him for all Blessings. I do not remember what the exact passage was, but I do not think it was important, because there are a lot of psalms that have a similar pattern. The pastor went on to say we should act the same as David does in this passage and thank God even in bad times.