What do you do when you can’t run due to injury?

You will be in shape soon again.
But I hope you found out in these 6 month why you got the injury in the first place so that will not happen again.

Try walking.

My running injuries were always lower body, so I would focus on my upper body. Like being able to bench press my body weight a certain number of times.

One could also focus on dead center body, like I do using my right hand, not a center number of times, but rather until fatigue and shame.

See a good - movement pattern oriented - physical therapist. For athletic purposes, things just don't heal on their own. Rehab is just as important if you want to return to running.

Rage.

Woe is me.

All of my life has been a waste.

Get in the gym and watch your diet

1) Elliptical, every day, as much time on it as I spend running. If that doesn't work due to pain:

2) Stationary bike, same volume as above. If that doesn't work due to pain:

3) Pool running, same volume as above. If that doesn't work due to pain:

4) Walking

Swimming. It's a non-impact aerobic workout.

Improve your running form and see if you can find muscle inbalanced.

Rowing.. I have a C2

Besides the calorie burning cardio stuff:

Up all the bulletproofing exercises/focus. Especially the ones you know are best for your weak links.

Nordic hamstring curl,

Tibialis/ Ankle stuff,

VMO exercises,

Negative calf work and other plantar/and Achilles exercises.

Etc.