Sometimes we make resolutions that aren't very realistic; they're only wishful thinking. And often we make resolutions without ever thinking about how we'll achieve them. We shouldn't be surprised, then, if we fail.
But sometimes we make resolutions that are good, ones that would make us better people if we could only achieve them, and yet we fail. We're like a man with a broken leg trying to climb Mount Everest; no matter how determined we are or how hard we try, we still fail. Even the Apostle Paul declared, "I do not understand what I do.... For I have the desire to do what is good, but I cannot carry it out" (Romans 7:15,18).
Why is this? The reason is because we don't have the moral and spiritual strength to stick to our resolutions. No one likes to admit this; we'd like to think we can conquer all our problems if we just try hard enough. But we can't, because down inside something is missing -- and that "something" is God's help.
Ask God what He wants to do in your life. Then by faith open your heart and life to Jesus Christ, and turn to Him for the help you need. God accepts us just as we are, but He also wants to help us overcome things that drag us down. May Paul's discovery become yours: "I can do everything through him who gives me strength" (Philippians 4:13).