It took about six months for me going from sedentary (3 yrs) to running two miles or more non-stop. It was difficult for me because I had never run in HS or college. I joined two running groups and got support from people at my gym—that was the real key! I probably would have given up if I had tried to go it alone.

Tell someone you see daily/weekly that you have made it a goal to start running! Get a rally going so you have enough momentum to reach your goal. Fitness sites like Nike Running or Fitocracy are great places to track your progress and get encouragement from others. Good luck!