Dealing with a "lower body injury" while dealing with cancer/back surgery rehabilitation

I'm rehabbing hurt.
Before I left GF Strong for home late last week, the doctors and physios assessed that I had tendinitis in my knees.
How cool is that? It almost sounds athletic.
The good folks at GF said that the pain was coming from both fatigue from rehab and from poor walking form, due to me landing all too often on locked knees. They tied that to fear of my legs buckling, and, I hate to admit it, but that's more than fair.
Ice and rest is the treatment and, after my discharge Thursday night, I tried to take it easy for a few days. We've hired a physio, Paula, who will come to the house to bust my behind, but she suggested that I spend a week or so getting adjusted to being home before I get back to a regular workout routine.
Much of my first few days at home was spent hanging out with Charlie, the 18-year-old daughter of Carol-Ann's brother Chuck. Charlie, who lives in North Carolina, is one of my favourite people on the planet. She's scrappy and fun. And she's brave as can be -- there was all sorts of family stuff going on right when Carol-Ann and I were getting married, and Charlie, then 15, came up here all on her own for the ceremony. That was a big, big deal for Carol-Ann, and I'll be forever indebted to Charlie for that. (Read: I'll bail her out of whatever trouble she might get in and EVENTUALLY let her parents know about it.)
The timing of my discharge couldn't have been more perfect because of her arrival.
Charlie left for home today and Carol-Ann went back to work, meaning that I got to spend my first full day at home. I had hoped to go to Canada Games Pool to do some laps, but chickened out. I did get in some stretches and strengthening exercises, and me and my new best friend Walks (pictured above...a little something we purchased prior to departing GF) took a walk around the block.
It's scary. Stretching and strengthening at GF is generally done on raised mats; I did it on the floor at home today, and we had a couple of limited sessions at GF about getting up off the floor.
But I want to be known as a battler, and I want to get better and the only way I can do that is going outside my comfort zone.
For what it's worth, my knees are feeling better. I shouldn't have to ice them too much tonight.