Stress Fracture

Well...talk about a wrench in the wheel. My training was going great and I was on my way. I am a competitive person and some what stubborn...perhaps it is the mixture of Irish and Mexican in my blood. I continued to run and incease mileage despite the pain in my foot. See the thing is, it didn't hurt while I run, it always hurt later on and first thing in the morning. This past Tuesday I was confident the pain had gotten better so there I go...running my fastest time for 6.5 miles yet. Now....3 days later....my foot is bruised and swollen, I am barely able to walk and I am getting and MRI this afternoon. Doc says ive either done tendon damage or I have a stress fracture in my foot. Most of the swelling is one the top of my foot and the side around my ankle.
This is very devastating and discouraging for me. There is no high in any other activity like a running high. It looks like I won't be doing much activity for a week or so and then I can do some swimming or biking. What I am worried about is ruining all the progress ive made this far. I am scared of gaining the weight back and getting out of shape. How can I overcome an injury that makes even walking difficult. Any advice or support would be greatly appreciated. I am really bummed.