I find that writing things down or placing positive comments/thoughts you have had about yourself around you is a good way to keep yourself from sinking into negativity. Keeping yourself accountable for negative thoughts and locating them before they override your brain is also really important, learning to recognize when the negativity is increasing and think positive things to focus on instead. For some people picking one good thing a day and remembering it as the day progresses is a good start and eventually you'll adapt to seeing it naturally. Also the people around you and your environment is important, if people are constantly putting you down or constantly "chaotic" then that won't help you. Support is a really good thing, remember you aren't alone and things won't seem so difficult.