This is an excellent idea. Living alone can help create an "echo chamber" (for lack of a better term) for negative emotions. Dogs (especially trained companion dogs) almost never contribute to these negative emotions.
Having someone/something to care for and who depends on you is sometimes a substantial boost to one's psyche.
Yes. I suffered from clinical depression years ago, and the number one thing that stopped me from ever harming myself was knowing that my cat was completely dependent on me. Even if I had arranged matters so I knew I would be found before she could starve or anything, I knew she wouldn't understand why I was gone. Those thoughts always triggered a huge sobbing jag, but they kept me alive.
These are all interesting points. In terms of caring for something, and something being dependent on me, I know that this would stop me wanting to kill myself so much - but it would be out of guilt. I already have that feeling for my mother. I want to find a positive reason to live, instead of what I see as a reverse negative.
The traveling thing - it's funny you should mention that. A month ago I did exactly this. I've left my business running and I've gone to another country. I am trying to spend as much time as possible volunteering, to help other people, as I thought this might help me. So far unfortunately I have felt very bad here. I am not entirely sure why. I will be here for another 2 months before I return.
A friend of mine did that and since he had to walk the dog, met many other people with dogs and in so doing met a lovely girl and they're now happily together with both dogs.