I found group emails helpful. Sent them every so often updating friends on my treatment. I am sure some appreciated it, they didn't want to ask but wanted to know.
I am retired so I can't help specifically with advice about going back to work. However overall I found I wanted people to ask me how I was going. I found it odd and a bit hurtful when people didn't ask me how I was going. No doubt people had various reasons for not asking. So when you go back to work it might turn out you appreciate being asked what happened. There are a lot of kind caring people out there and their supportive interest in you will help you.
i couldn't have worked through my treatment in any event. Everyone is different, some people cope better with the treatment than others, but it is very fatiguing for some of us. Nursing is hard work and you are on your feet most of the day, not for everyone while undergoing cancer treatment. Very best wishes for the treatment. Karen