I had to greatly weigh the pros/cons for myself. Originally, I was wanting to get another dog FOR Jackson but I think sometimes it can be a bad idea to do this just to give your current dog a friend. I had to think to myself... do *I* really want a second dog? Financially, could I afford to groom two, feed two, provide vet care, etc? What if an emergency came up with both dogs at once... I probably couldn't afford it, to be honest. I am 20 years old and still in college. I can support Jackson on my own, but not so sure about another.
With my current lifestyle, I really enjoy bringing Jackson places with me. I am a young single girl and I like to travel and when I can, I bring him with me. Every summer, we vacation to Gettysburg for example and he comes. I visit over my dads house once or twice a week and he has two dogs and a fenced in yard, etc. When I go to family members homes for holidays, I bring him with me, etc. If I just go visit a close friend at their house, he comes with me. He's my constant little companion and I really don't think I could do it with two of them and I'd end up leaving them home more often than not (because I wouldn't want to bring one, and not bring the other). I have a really tight bond with him (and I'm not saying this can't occur with two dogs, obviously it can)... but it's just something I'm not sure I want to 'break' right now or change.
I know I will have a second eventually... but now is not the time. Yes, Jackson loves other dogs and he probably would be happier with a friend (or maybe not, you never know). But I make sure to get him to the dog park once or twice a week, he visits my dads dogs often, we go for daily walks (with other dogs, as I am a dogwalker), etc, etc. He gets a lot of training, attention, socialization and doggy playdates. He's a very social dog so I'm not too concerned about that part of it.
I think I will know when the time is right but for now, I've learned to be very content with just Jackson and I. It took a lot of realizing though... I think I was so obsessed with the idea of a second dog for a while that I forget what I have right in front of me. I have a GREAT dog who is capable of nearly anything I'd ever want a dog to do. My life is very easy with him right now... he's a go-with-the-flow kind of dog, and while he does require quite a bit of exercise/activity and is very active, at the same time he is also a laidback dog (MOST of the time). If I wanna sleep in til 10am? He's right there with me. Skip a walk for a day? Usually no problem, just make it up to him by playing fetch at home or doing other indoor games. Things like that. I'm just not sure I'm all that ready for a new pup to change my routine around.