All parents go through difficult times with their children. Some when they are very young, others as teenagers, and many into their child's adulthood. We never stop worrying about our children, even when they are grown. Each stage can be challenging no matter what the issue. What one parent may perceive to be overwhelming, another will handle with ease. This does not make anyone's path more or less difficult, it is just different, and everyone's ability to handle situations they come across varies.
Look for the positive in your situation, I know it is not easy. Don't be quick to judge others who seem to be having an easy time with their children. You never know what is going on behind closed doors. Whether you are dealing with physical illness, mental illness, or disciplinary issues with your children, remember somebody is enduring something worse.
An easy journey is not always a successful one.