Will run again..
The 3 x 1 mile was my way of breaking up the work and less focused on hitting a specific pace target. 8 min per mile just felt right. Any slower and it felt like I was plodding and much faster it felt like I was pushing it too much. I did the workout on a treadmill set at a slight positive incline (1%). That said, I did wear an heart rate monitor and saw my heart rate climb to 180 bpm (90% of my HRR). It dropped quickly during my 2 min walks, back down to less than 120 bpm. My other runs have been on the track, there is a really nice 8 lane track about a mile from my house. I have found that anything with even the slightest bit of downhill feels creepy so I am sticking to the track or treadmill for now.
Also, your advice on using shorter intervals is well taken. I started with 100's, 200's and 400's moved up to 800's and then I jumped up to 1600's too quickly. I should be sticking to the shorter intervals. At this point it is less about building fitness through running and more about building up coordination, strength and the ability to run.
To give you some perspective, two months ago walking at 15 minute miles produced 150 bpm which is firmly in the aerobic training zone. You will run again.
It will also take a while to regain a natural walking gait. Mine still requires attention, particularly if the injured leg is tired or there is any kind of downward incline to the terrain. It just takes time.