Having lived with my family, a roommate, a husband and a cat I much prefer the company of my cat.
A cat will never judge you.
A cat will love you even when you don't feel particularly loveable.
A cat won't try to change you, they like you just as you are.
You don't have to worry about hurting your cat's feelings, they don't care what you think of them.
A cat doesn't hold a grudge. They have a short memory and they get over things quickly.
A cat will never yell at you. The most you can expect is a loud "MEOW"