[RustyMilo]

I have a 3 year old yorkie. I live with my boyfriend and his family in a decent sized house and we've lived here for about 2 years. Recently I went away for a week to visit family with my dog and while we were gone my boyfriend's sister who is 15 adopted an 8 week old morkie. My dog doesn't like the new puppy, if the puppy comes near him he jumps on the couch so it can't be close to him. I understood being upset about a new puppy but it keeps getting worse. They have only had Bear (morkie) for about 2 weeks and my dog is starting to act horrible. They sleep in different rooms in the house and for the most part only interact a few times during the day to not upset Rusty(my dog). Now they seem to be dueling. My sisterinlaw likes to go out with her friends so the dog either stays in the crate barking for hours or I take it out and let them run around in common area. As they run around they each pee on everything. My dog is trained on puppy pads and has been fully potty trained for 2 years but now it seems he is acting out. He pees on the floor, on the doorways, on the bottom on the dining room table and chairs, and even on the laundry basket. Hes got horrible behavior now and poops where ever he feels necessary and barks way too much. I'm exhausted from trying to stop this. He seems mad at me and won't come near me if i was holding or petting the puppy. I don't know what to do. Everyone in the house keeps saying let it run it's course but I'm getting sick of training a puppy I didn't want while cleaning up after 2 dogs and having my baby hate me. Please help. Any suggestions will help!!!