Let me assure you, everyone has a cross to bear, a burden on their shoulders and their own struggles. Such is life that we consider no one and do not suffer their consequences, until we are in their shoes.
If today is anything like that for you, know that you are not alone. Know too that you can change your mood or your situation. Just do what your heart tells you to do. Fight and work to make the difference you so desperately seek. Even if it does not work out, at least you tried.