Hi, Tristeve -
Like David, I am a cyclist and was riding 100+ miles a week before my diagnosis and tx. As if the surgery wasn't enough, the radiation and chemo meant I've been off my bike since June. I've only JUST started riding my mountain bike on easy trails for about 45 minutes a go, a couple of times a week. The first inklings of energy are just starting to return, and I am about 10 weeks out of treatment...and there are days when I still just want to lie around and rest because of the fatigue, so I just let them happen as they will.
In short, this recovery takes a much longer time than probably any of us was ready to face when we got into this! So hang in there -- you WILL be back, but you need this time to heal and recover. It's hard.