Prov. 3:12: For whom the Lord loves He reproves, even as a father corrects the son in whom he delights (NASU).
If we look at suffering as something to be avoided, we may miss some of God's greatest work. This passage tells us that some suffering is God's effort to correct us, and His vast love for us allows it. Suffering can be a sign of God's love!
Suffering also gives us a chance to display God's glory. The apostle Paul had a painful condition he called a "thorn in the flesh." We don't know what it was, but we know it bothered him enough that he prayed for its removal three times. God did not remove the "thorn," and Paul was convinced that his suffering was an advantage to him because it kept him from becoming conceited. God told Paul that Paul's weakness revealed God: "My grace is sufficient for you, for my power is made perfect in weakness" (2 Cor. 12:9 NIV).
When you feel you were not cut out for parenting, remember that when you are weak, God can fill you with His strength. When you rely on your power, there is no room for God.