Why do some people answer sincere questions with harsh or mean answers?

I recently began using this site. I recently asked a question about getting a dog, now that I'm not working and my kids are in college, and my husband travels extensively, and he doesnt particularly want another one. I was called ridiculous my one responder and selfish by another, and one suggested that with my selfish way of thinking she's surprised I even have kids in college. And since my husband was the only one bringing home any money I need to respect his wishes. I do agree that I should respect his wishes, but I left my job due to cutbacks, I raised my kids, while working full time w/ a husband who was never home. We do not need my income anymore as we are blessed that my husband has a very good job. I wanted to rescue a dog because I'm lonely and my passion is dogs, and dog training. People, you should not make assumptions about other people that you don't know. I am far from selfish, and far from lazy. Please choose yourds words more carefully, as you never know what someone could be going through. If you don't have anything nice...or helpful to say..say nothing...