Love is the greatest alchemy there is, the most profound science of transformation. If you love, your whole energy is gathered, becomes one-pointed. Doubt needs energy, shame needs energy, fear needs energy, self-condemnation... they all need energy.
If you do not love, then all these things can go on living in you; you are nursing them. As the great miracle of love happens, all the energies rush towards love, just as all the rivers rush towards the ocean. Doubt remains empty, and without energy it is dead. It was your energy that was keeping it alive.