I know this might sound a bit wacky, but I would actually suggest getting a young puppy! I had MAJOR baby blues before we got Archie (couldn't afford a baby) and getting him helped so much...he IS my baby.
It's looking more and more likely now that Si and I may never have kids. I'm just getting too sick. But I'm kinda okay with that. Archie is my baby.
If nothing else, having a young puppy is so much hard work (yep, like a baby) that it takes your mind off other stuff.