Here is the second part of my rephrase. Hopefully I can send it to you, Writeacher! Thank you.
1) Then he likens both his family and friends to the horses for their shape and disposition (?). Though more civilized and endowed with the gift of speech, they seem to use their reason to multiply their vices. So these qualities do not make them any better.
2) He, however, acknowledges to his horror and disgust that he is exactly the same, or even worse, than the loathsome horses when he observes his face reflected in the water.
1) Then he likens both his family and friends to the horses for their shape and temperament. Though more civilized and endowed with the gift of speech, they seem to use their reason to multiply their vices; therefore, these qualities do not make them any better than ______.
2) However, he acknowledges to his horror and disgust that he is exactly the same as, or even worse than, the loathsome horses when he observes his face reflected in the water.
You're very welcome. Remember that if you have questions about why I made any changes, be sure to ask.