Hi Georgie
I had a similar issue when I went back to work after I finished chemo and radiotherapy. Apart from the fatigue I would burst into tears at the drop of a hat - some work mates were very supportive, some acted as though nothing had happened, some just wanted to tell me about their breast cancer experiences but had no interest listening to me or sharing mine. I was tired, emotional, resentful about having to work, anxious about my future and not keen to try anti depressants as I was worried about what side effects they might have too. Saw my GP and said "I think I'm depressed!" she referred me to a psychologist under a Medicare funded mental health programme. I think I would have gotten better over time on my own but i did find it really therapeutic to see someone who would just let me talk and cry with no judgement made. I think I did 6 or 8 sessions with her. Since then I have also started meditating which has helped me feel calmer, less anxious, more able to live in the moment.
I think we all experience the fear and sadness that you are feeling and that's pretty normal after what we're going through but there is help out there and you dont have to try to manage it on your own.
I hope my experience might help you a bit
Take care
Marian