What should I do? I'm not sure if I molested my dog and I feel horrible.
Why would you think that you molested your dog?
I show my dog a lot of affection and I've always liked animals more than I liked people.
Liking animals more than people is fine and so is showing them affection but you said "molested". If you did something sexual to your dog you have some problems going on mentally that you need to work out and you really need to seek some help. If that's the case I really hope you do, both for your sake and the dog's.
Has anyone licking their pets considered to be a sign of affection?
Dogs lick people as a way of showing affection. It is not something that is appropriate for people to do to their pets. If you feel that you have molested your dog, you know that is wrong and you should never do something like this again.