It may not be an organization doing good work in the community, but you can't do sustainable good for others if you're not practicing self-care. Though getting something done after pushing through may be satisfactory, it also makes you susceptible to colds, viruses, and other forms of illness.
For me, that means binge watching something mindless on Netflix (like "Reign," which absolutely fits the bill) while playing a silly browser game and working out at least twice a week. But if that doesn't sound like pure bliss, explore your options. Whether it's an intense workout, dinner out with friends, a long soak in the tub with a beverage of your choosing, or a couple hours of video games, self-care doesn't have to be expensive. Heck, if you love to walk outside or watch videos of puppies, it can be free. Whatever it is, take the time out to care for yourself so you can care for others.
Don't believe me on this one? Well, check out the TED playlist on the subject or Lifehacker's take or Psychology Today. Stress, like that caused by your job, home life, political realities, etc., is really bad for your body (Google Scholar backs me up here with more than three million papers for the search). Self-care is a way to re-center, re-evaluate, and give yourself some space to exist in the moment. Cold season is upon us, and I'll say it again: you can't effectively fight for others if you're ill yourself. Be gentle.