Here’s an article with an anecdotal story of a woman who would bad mouth her husband to her friends.  She found the more she talked poorly of the fellow, the farther and farther he got from what she most desired from him.  Not really a surprise.  If you haven’t read Influence by Cialdini, I highly recommend it.

If all you talk or think about is negative, all you will see will reinforce your perception.  You may not think your actions will reflect those conversations and inner thoughts, but they always do.