Why is my 5 year old dog acting this way toward the puppy?

We've had Zoe for almost a month now. The main reason why we decided to get another dog is because our older dog, Brody, could use a friend. He is a very shy dog, afraid of loud noises, and sometimes fearful of other dogs. We really wanted him to come out of his shell and experience canine companionship. Well it's been almost a month now and he's had plenty of time to get used to the puppy, but I'm not sure if they are getting along or not. The Boston Terrier puppy is super hyper and whenever she tries to play with Brody when he's not interested her nips at her. He doesn't actually bite her.. He bites the air. They sometimes play, chasing each other in circles over and over again. But they never get close to each other. My shih tzu always backs away from her. I thought they would be sleeping together in the same bed by now! Will it be This way forever?