This is definitely something I can relate to and go on about. After Kona this year, I had to lay low for quite some time because of a foot injury (didn't get to finish the race). It's a long process mentally, physically and emotionally.
I try to break the come back to injury in weekly increments. Luckily for me, I was headed right into my off season so that helped... a little.
Each week I look at what I can do and work with my coach on a daily/weekly basis for things I should focus on. For the first 4 weeks (yup!) I did literally nothing. I read a lot of books. Then we progressed with some swimming and seeing how my body felt with the increased activity. Etc.
The goal is to work weekly and see what if you can handle the slightest increase in training. It's a slow progression but to break it up in chunks is better for the mind mentally. I also worked on a lot of other aspects of myself as an athlete - mental, emotional and well, figured out why the injury happened in the first place.
If you have specific injury issues PM me. or other info you want, let me know!
Angela Naeth http://www.angelanaeth.com http://www.iracelikeagirl.com