Hi Smear,
I'm writing because it seems like this is really getting you down. So, first I want to just empathize. I get it. Like you, I'm addicted to cycling, climbing, skiing, hiking, and so on. I need regular vigorous exercise, or I'm a completely different person.
I have also dealt with many operations and injuries over the years, including three knee surgeries (two on one knee, one on the other knee), one ankle surgery, and two foot surgeries (one on each foot).
Here are some hard won lessons.
1-In some sense, we are all adaptive athletes. I don't want to minimize the astonishing accomplishments of real adaptive athletes, like the people who compete at the para olympics, but as we get older, if we want to be athletic, we all need to adapt. For example, I got through a whole season of ice climbing with a broken finger--I just taped my fingers together, changed how I held my ice tool, modified my technique, and accepted my limitations. Or, whenever I have lower leg injuries, I do a huge amount of core work. Or, when I had a hernia surgery, I wrapped a towel around my waist, and did ankle, hand, and shoulder mobility stuff! There is a great deal of fulfillment that comes from not giving up, doing your best, and staying active, even if it's not perfect, or the same as you could do before (I'm 51).
2-Stay active. Don't stop. Consistency is sustainable. Binge and purge exercise is not. The best way to get real exercise with a lower leg injury is with Concept Ski Erg. Stand in one position or sit down. It feels great and you can get the endorphin boost and mind clearing effect that you need. Running in a swimming pool with an Aqua Jogger is also great. You can get a ridiculously intense low impact workout.
3-Embrace recovery, streching, balance work, tissue work, yoga, Tai Chi, and stuff like that as real exercise. Invest in these things, and your body be much healthier. You will become a better athlete.
4-You should do whatever you need to limit the pain while doing the sports you love. Basically, why are you in tight road cycling shoes, tight alpine race boots, and tight XC boots? Get a pair of Sidi Mega road shoes, or wear wide gravel or mountain bike shoes with softer soles and SPD pedals. Before you dismiss this advice, ask yourself what's worse. Riding on the road with mountain bike shoes and SPD pedals, or not riding at all? Likewise, get some wider, softer, alpine boots for skiing. Yes, the performance will not be the same, but I think you will ski much better in looser more comfortable ski boots with no pain than in tight race boots with pain. Perhaps consider something like at Atomic Prime with the liner molded to make space for your metatarsals. For XC skiing, try a pair of the Fischer backcountry boots--they are wider and more comfortable than regular XC boots. Weight doesn't matter. If you are pain free you will perform.
5-The insole industry is full of ridiculous claims and hype. It borders on fraud. I read a peer reviewed study that compared off-the-shelf insoles to the most expensive physical therapist and medical doctor created insoles, and found no differences in injury prevention or pain relief. I reached the same conclusion over the last thirty years of buying insoles, spending litterally thosands of dollars. Use what feels comfortable. You are the best judge of what's best. Perhaps could buy a range insoles, from 20$ insoles to 200 $ insoles. Thick, thin, high arch, low arch, soft, hard, etc. Use them, cut them, modify them, experiment. Find what works and reduces pain.
OK, rant over.
Good luck!
Bruno