Oh boy, after reading this entire thread, I'm not seeing a happy outcome to all this. Seems like you're both being unreasonable, and have entered a cycle of blame that will feed on itself until something drastic happens.
He may have lied to you or misled you, but you have no legal right to disallow him from having a girlfriend and apparently no legal right to disallow him from owning a pet. You can't restrict his or his girlfriend's comings and goings.
With the noise issue, unless it's consistently excessive, I don't see what you can do. Invest in a fan.
I sympathize. I do. I remember what it was like rooming with others who had different lifestyles from mine. I have a feeling I'm a lot like you. I am always careful not to inconvenience others if I can help it. But the reality is that not all lifestyles are compatible, or at least can't live in complete harmony. Remember that everyone has a different perspective. What you find is thoughtless and disruptive behavior, he likely finds completely acceptable and normal. What he thinks may be ridiculous restrictions you imposed on him, you may think are completely reasonable.