Can my cat survive without a playmate?

We had two cat. My girl cat, one of the movers took her or she ran away when the front door was left open by my bad nephews. Any way we've had the one cat for 3 years does he need to have a companion or can he manage alone? I really don't want another cat I get attached to easily. So can he survive being the only cat? My husband wants a dog as a matter of fact he adopted a dog(puppy/golden retriever). How will my cat react? Will this work? Since we've had our cat for 3years. I begged my husband to wait but he wanted a dog now.(pray for me) So can a cat and a dog(puppy) get along?