Hello, it's nice to talk with you again!
You are doing the right thing by not acknowledging your supervisor's behavior. From your description of him and his behavior, it sounds like he is not able to relate to others very well because of his poor self esteem. He must feel so bad about himself that he focuses totally on his perceived "faults" of others and trying to bring them down so he doesn't have to face how he feels.
You are absolutely right that by ignoring his behavior and being pleasant at work you can win everyone else's friendship and prove that your supervisor is wrong with what he says. But I also think you have more power than you think. Your supervisor does not realize that in his attempt to make himself look better than everyone else by running them down, he makes himself stand out as a person no one wants to be near. So in a way, he does the very thing to himself that he is trying to avoid- making everyone dislike him. And your co workers see it very clearly. They may feel sorry for him or dislike him but they do see him for what he is. Since your co workers do see him for who he is, anything he says about you will automatically be ignored. No one is going to trust anything he says. Even your new co worker picked up on it right away. So your supervisor must be pretty obvious in his attempts to run you and everyone else down.
Your strategies for dealing with this are good and solid. It is not easy to deal with someone who tries to get under your skin at every turn. But try to see him for what he is- a very sad
person who has no self esteem that is trying desperately to feel better about himself at the expense of others. Everyone sees him for what he is so he can't even be deceptive in what he does. He feels that bad about himself.
When he does say these things about you, you may want to try asking yourself if you feel they are true. Of course they are not, but by asking yourself you allow for any doubts you have about your own self esteem. And if you question yourself about what he says, then working on your own self esteem will help you develop an even stronger barrier against his words.
Overall, though, you are doing a very good job handling this guy. People like him can get under your skin, making it hard to focus on your job and develop good relationships at work. But even through all that he tries to do, you are focused and making a great effort to cope with his problems. Keep on doing what you are already doing and when you feel it gets too much, talk about how you feel. The support you get can put you back on the right path.