A mistake I made was to 'retreat' from horses when I felt negative or down - felt as if I had to 'protect' the horse from my 'negative' energy. Horses naturally absorb this 'negative' energy and transform it into something positive - this can be felt when one takes the step and touch a horse. Touching a horse is being in the presence of a 'soul' who is always present - who always lives in the Now.
The horse is only concerned with your intentions - the color of the blood in your heart - if it is 'dark' the horse will look after it's own interest. Your emotions a horse can deal with.