Step 1: Consider the possibility of cutting them loose. It might be a harsh choice, but if the bad outweighs the good that these people bring to your life, it may be time for an act of self-care by freeing yourself from the negativity of someone who is dragging you down. If the negative person is draining your energy, causing you to dread scenarios where you know you'll need to deal with them, or putting you and others down, consider cutting the cord. It needn't be dramatic or harsh, and it might be difficult as well. But sometimes, you need to make your own sanity and wellbeing a priority!
Step 2: Find ways to cope with their negativity. There are probably a few emotional vampires that you can eliminate from your life entirely. But there may be others, such as relatives that you have to see along with the ones you really want to see, or co-workers over whom you have no control, that you really need to interact with occasionally whether you want to or not. Even if you don't have a choice in the matter of dealing with them, you can choose HOW to deal with them. And that can actually make all the difference! Try to accept them the way that they are. Understand that a negative person is probably a miserable person, and remember that 90% of what they're griping about is definitely not personal. This is just who they are, and their behavior is about them -- not you. Take it all with a grain of salt and allow the whining to roll off of your back. When you do have to deal with them, stay positive and upbeat; even negative people want to be treated with friendliness, and you might be surprised at how some of them can really be disarmed by a warm smile or a light friendly conversation. Small talk can also serve as your barrier to some of the deeper complaints that they wish to share with others. This really does work in many scenarios, so try it!
Step 3: Seek positivity within their negativity. While this might seem like a major oxymoron, it's actually not. Many times, negative people are just unhappy souls who use their pessimism as a protective barrier to keep pain and rejection from penetrating their thin skins and wounding them. It's also very possible that those with whom you are close, are also being negative or critical in an attempt to shield you from some danger or trouble that they perceive. To them, their thoughts are real and their comments are used to defend and protect. Analyze the situation and try to determine if the negative person is a downer about every subject in the world, or if they're especially prickly about only certain topics. Remember that this need to protect, while strange, may also bring out some valid points for you to consider. Those who are good at seeing potential problems and voicing those issues to you are actually trying to be helpful. It might be that they care about you, or want what's best for everyone. Whether their negative feelings have weight or not, seeing it from this perspective can help you to develop more tolerance as you understand better where it comes from.
Whether the intentions behind your "Debbie Downer" are positive or negative, it's important to understand that there's often a lot more going on than the surface of the situation shows. If you're unable to remove the negative person from your life, ask yourself why they must stay. And then, in order to remain positive yourself, use your optimism and positivity as tools to deal with the negative energy and words coming from this person. At the end of the day, the only person that you have control over is yourself -- make the most of what you've got!