My dog's terrified of the puppy!

Lulu Belle

I need some advice...I've had my dog for two years, female mutt. When she was a few months old I thought about getting another puppy but changed my mind when she showed aggression to a puppy, biting its neck and shaking it. I hadn't thought of getting another puppy since then, but I found an abandoned stray (also a mutt, and this one male) and have kept him the last few days. I haven't totally decided yet whether I'm going to keep him or not, but I got him his first shots anyway just in case I do.

He's so much smaller than her (the vet said about 3 and a 1/2 months old), that I was afraid that she'd be aggressive again. I was completely wrong, she runs away from him with her tail between her legs and starts shaking. My dog has a lot of anxiety problems. She's afraid of anything and everything. Paper, plastic bags, strange people, all other animals, furniture that doesn't have cushions on it (she loves the couch and the bed but if her toy ball rolls under the kitchen table she won't even try to brave the chair legs and get it). She's even afraid of her dog bowls and will only eat one kernel of dog food at a time, picking it up like it's a bomb and then running across the room and eating it away from the bowl. She always looks like she's about to sprint when she drinks water.

I don't know why she's like this. But those problems aren't that important, just trying to shed light on her general attitude. I really want her to bond with the puppy, as I would like to keep him. But I have no idea how to get her to socialize with him. She looks so scared when he tries to play with her and just runs for my lap. I'd almost prefer she was aggressive, instead she looks like she's going to have a panic attack when he's anywhere in the same room with her. Any advice on how to get them to bond would be great!