Don't worry about comments made about your chicken management by someone who knows nothing about your setup or your habits. Not everyone realizes that sometimes chickens just up and die despite the best of care. Now, on to your questions. Chickens are more of a flock animal and yours would probably be happier (if a chicken can truly be happy) with a flockmate or two. I would try to find one of a similar age or size to bring home, rather than chicks. An older chicken doesn't usually take well to babies that they haven't raised. Check Craigslist, your local paper, ads at the feedstore, or with friends that you know who have chickens to see if you can get a friend for your pullet.