roommates boyfriend is always over, help!!!

Hi, im not sure if im justified in feeling upset over this but my roommate constantly has her boyfriend over. Ive just moved in with her maybe a month ago and she is very sweet but we already have so much going on in our apartment a whole other human being is a lot. She has two decent sized dogs and two birds and I have two cats that stay in my room. Her bf just comes in and out multiple times throughout the day im not sure maybe to take care of her pets or something but he doesn't go home he sleepover and I feel like I can never walk out of my room without having a sweater and sweatpants or my robe on because I never know when he is going to pop up or if he is out in the common areas or maybe in her room with her bedroom door open. Also our bedrooms are right next to each other so I hear everything. Her, her bf and those two dogs in a room right next to mine is very loud. I also don't want to hear their intimate time each night. I signed up to live with a woman not a woman and her man. Also their things are everywhere in the common areas so its not easy to use them. I eat and study in my room because the dining room table or living room is always cluttered. I feel like an uncomfortable third roommate to them and like im just staying in their place and like her boyfriend is more of a resident here than me.