Whenever those negative moments happen, I simply cry it out for a while to get it out of my system. When I noticed myself over analyzing, I will stop 'entertaining' those monkey voices in my head and forgive myself, forgive others. Finally, I remind myself that I am only human and am allowed/entitled to feel the way I feel. Next immediate action is to take a good shower with the motivation that after the shower, I will do something that is focus on me and not to 'listen' to the negativities...
We are allowed to breakdown once in a while... That doesn't mean that we are not positive people... We are only human with feelings...