I love animals, too and I can understand why some people prefer them to people.
I think that part of the reason is that when you have a pet, not only can they give you unconditional love, but you can also give it to them.
Unlike the people in our lives, we don't have expectations of our pets. It's impossible for an animal to do things for us, so they never let us down. It's not reasonable to think "I do this, this and that for you, so I expect this, this and that from you." As a result, resentment never builds up between us and our pets, as it might with a friend, partner, colleague and/or family member who we have many expectations of.
It's a relationship where you can keep on giving and caring, expecting nothing in return - this is real love and I think that's why it feels so good.
Bluey