As many people here warned us, the first few weeks out of treatment were the worst. But after that, there were steady signs of improvement. He finished in May and while he certainly is not back to where he was, he is SO much better with his energy level(and other things).
I agree the nutrition is very important and when you feel ready to try to slowly work on building up your endurance. His MD suggested daily walks and it was good for both of us to see the progress of him being able to do more each day. Start small and build it up.
But this is very early for you, so try to be patient and give yourself some more time to heal.