Don't depend too much on anyone in this world. Because even your shadow leaves you when you're in darkness.
If we think about it, relying on people around us is in the same, opening up ourselves to the risk of being disappointed by them as well. No matter how any of may try to be, no one is perfect, and no one will ever be. In this world there will be moments where we may feel like we are alone, but we truly never are, because God is always with us.