You might wonder what I'd say differently on this topic since there are already piles of content floating around the internet. But fasten your seat-belts and keep reading if you want to hear about DESTROYING negativity. Both it, and the people who spread it. Why, you ask? Because it deserves to be destroyed. There's no extra space for bullies and negativity in our world. Especially in this age and time. Look around you. Look at the world you live in. The minute you check your phone for news updates or (more traditionally) pick up the news paper in the morning, you read about violence, war, corruption and terrorism. This is the time when you need to do all you can as individuals to destroy even the smallest negative acts you see around yourself. Keep yourself clean by shoving these negative people and their comments out of the window. You might be making the smallest difference by destroying them but a difference, nonetheless. And without going into too many details, the best way to destroy them is by making two things known to them:
You are fully aware of what they're doing whether or not they themselves realize it.
They are no longer welcome to be a part of your life and continue doing what they're doing.
As usual, before coming to the "how", I'd like to inspect the "who" of the situation. Who is being negative towards you. The answer is simple. Anyone who says/does anything to spoil your mood and ruin your day. Basically, a bully. The range of bullying may vary as we're mostly dealing with the "verbal" kind of bully. You can read more about bullies here.
But coming back to the point, let's broadly classify all the people in your life as your "acquaintances" and "people who matter". This classification makes it very easy to decide whether or not you want to show someone the door. It's all a question of relationships and what future you see for the relationship. Do you think he/she matters enough for you to want them in your life or is it possible for you to completely burn bridges and let them go? People you're sure you won't miss, fall under the former category whereas the ones you feel deserve a chance, fall under the latter.
Let's consider, for example, an acquaintance who is being negative to you. This person could be your distant relative or classmate or colleague. This person could be picking at some perceived flaw in you or giving you backhanded compliments or making you doubt yourself. As long as you know that you don't need to have a future relationship with him/her, feel free to completely block them out of your space. Don't let even their presence around you disrupt your mood. The best remedy is to stay away from them and make it very obvious to them that you're avoiding them. If this person was intentionally being mean to you, he/she will understand what you're doing, feel defeated and stay away from you. But if it was unintentional and they value the relationship they share with you, they might try to get in touch with you and confront you regarding the distance. This is your opportunity to explain to them what their actions were doing to you. And if it's worth anything, they might stop doing it and you could continue to have them in your life.
Always make sure that you make it known when you're keeping your acquaintance at a distance. If you don't feel the need to indulge in a conversation with someone who isn't worth your time, don't. But they need to know what they're doing. If they get the hint and remove themselves from your life, well and good. If they don't seem to understand or mean to stay in touch with you for whatever reasons, you should talk to them before letting things go back to how they were. There can't be a second chance without a perfect confrontation. No relationship can work without free and open conversation.
Now let's consider some of the "people who matter" in your life who are being negative towards you. They could be your close friends or family. If they matter to you, you might want to continue having them around in your life. But that doesn't mean that you silently endure the b---s--t they throw at you time and again. These are the people who need to be destroyed in style. So that they, themselves see what they had been doing. The good old fashioned way of sitting someone down and having a one-to-one may not necessarily work in this case. They could either get too offended when you pour your heart out or they could feel even more amused by your reaction. And you don't want to give anyone any sort of ammo against you.
Your own best ammo against these people would be your reason. How could anyone gain a sense of satisfaction by putting down an extremely calm, collected and reasonable individual. If you smile at their remarks and kill their arguments with reason, they wouldn't stand a chance. If you manage to find the humor in the situation, their attempt immediately dies and painful death. If you only have positive things to say to them, you are in fact, killing their negativity with positivity. Easier said than done, I know. But imagine this. A family member tries to rub it in when you're the only one who couldn't attend a reunion. If you feel sore and sit in a corner and mope, they win. But instead, if you make it known that you're there in spirit and would love to see more pictures of everyone, they know they lost. It's the little things.
Asking questions helps. By counter-questioning someone, you force them to think about their stupidity. About the silly remark they might have passed. About the thought that provoked them to ask you something stupid. If they feel silly and stupid, they will be forced to stop. Try to never lose your cool and end up responding in a way that is amusing to the person trying to play with your head. Instead, turn the game in your favor and have fun with them. Get into their heads and play with their expectations from you. Try not to hold grudges or put them down, yourself. They will come around eventually. And in most cases, after having corrected themselves. If not, forget about consequences and have a one-to-one. Not the subtle kind but the kind where you make things crystal clear because believe me, these very same people would pee their pants when forced into a direct confrontation. You tell them, "This is how you've been treating me and I do not appreciate it. You're important to me and that's the only reason I'm even taking the chance to talk to you about it. I don't feel comfortable with your remarks and I hope that by telling you, you'll change your treatment of me. However, if you feel that I'm the one at fault and have offended you by telling you this, I want you to know that I'm totally fine with us not being in touch anymore."
That should do it.
In some cases people are confused about how to react because the person being negative to them is important to someone close to them. For example, if it's your mother's cousin who's being negative to you, and you know that this person means nothing to you but is important to your mother, then just because of your love for your mom, you might feel trapped and forced to be nice to this person. In such cases, you have to go directly to your mother or whoever it is that acts as the link between you and this individual. Because he/she could get affected by your reaction to this negative person. Once you establish how he/she feels, you can easily choose whatever course of action you feel would be ideal, based on the situation.
At the end of it all, try to be compassionate. Know that there's probably a very obvious reason for why someone is behaving in a certain manner. And their own insecurities come screaming out when they spread negativity. Understanding helps you to be kinder in the way you deal with them. Kill negativity and spread love! Enjoy!