This is why I'd love another dog. After my golden retriever, Ellie, died in 2006 (luekemia) I decided I wouldn't have another again because I didn't want Ellie to look down from Heaven and think I was replacing her. It's been over 3 years now though, and I've said good night to her photo/memory every night since she died, and will continue to do so... which I hope is proof to her that was very special to me and I will never forget her.
So now I've decided I would like a dog because it would help me so much, socially. It would give me a reason to go down the beach, or just out locally - to walk the dog. As already said, it's a good ice breaker too and people are more likely to start a conversation with you when you have a pet with you. They are also a good outlet for your affection, I find - it's nice to have someone to hug when you feel lonely/sad.
Dogs are great for people with Social Anxiety. And I am certain that Ellie would be looking down with one of those big doggy smiles if you adopted another dog. I'm sure she'd love to see you happy, and I'm sure she'd love to see a canine basking in all of the love that she had and still does have. You can never replace a dog, ever... They're all too different. I'll always love my Jesse who passed away about two years ago, but I've adopted another dog since. I bet if Jesse were to be looking down, he'd be happy to see that I was happy, that I was given love and company rather than holding back because he's gone. Jesse will never be even comparable to my new dog, Dakota, and vice versa. They both have eternal places in my heart, as do my other two dogs who were lucky enough to have known Jesse.
I rescue animals. Mostly dogs and cats. My new year's resolution was to rescue 50 dogs and cats from euthanasia, but by the end of April I'd rescued over 150 cats and 100 dogs... My main reason for being so, so loving towards animals is that unspoken bond and friendship that they provide so willingly. There are service dogs for anxiety, service dogs for depression, and obviously servicce dogs for much more... In my opinion, everyone with SA should own pets. Even my rats, rabbits and lizard warm my heart.
Without my animals, who knows where I'd be.