“Let your conversation be without covetousness; and be content with such things as ye have: for He hath said, I will never leave thee, nor forsake thee. So that we may boldly say, The Lord is my helper, and I will not fear what man shall do unto me.” -Hebrews 13:5-6
When you complain and grumble about your circumstances, you are calling into question the love of God and His goodness in your life.
Contentment in life is only found in the Lord. He alone can satisfy your needs and your longings.