"Right" and "Wrong" are man-made concepts and are subjective from one individual to the next. What's right in my eyes could be wrong in yours, and vice verse. A loyal friend is a loyal friend, and some beings just have more of a profound affect on our lives than others, no matter if they walk on 2 legs or 4. So don't ever let another individual's version of what is right and what is wrong intrude on what you feel in your heart and make you feel guilty.
There are many dogs and humans I would not shed a single tear for if they left this earth. There are some dogs and humans in my life that every bone in my body would break for if they left this earth.
"If you don't train them, don't blame them"