Oh my gosh reading your post has made me so angry for you!
As you’ve been diagnosed with CC you are now protected legally under the Equalities Act 2010, and you always will be. It is illegal for an employer to discriminate against you etc, and downright rude and unacceptable for her to not respect your one request. If you take a look at the Macmillan site under work all the guidelines are laid out. There are fact sheets for employers and line managers too. I’d send yours a copy soon.
If I were you I’d call your GP and get them to sign you off if you can’t face going in. Or speak with your HR department ASAP. You’ve had a scary diagnosis and you need to concentrate on you now.
I flitted between work after diagnosis, I went in but it was mainly to hand over stuff, then I got signed off for 2 weeks after lletz under GA, then I had the rad hyst and I’m still off 4 months later. Really I wish I’d have stayed off since diagnosis as I wasn’t much use at work.
I’m so sorry you’ve been treated like this. Your employer really should be respecting your wishes at this very difficult time.
If you take a look in the ‘post treatment’ forum there is a post about what to say in a new job. A guy who is a HR lawyer specialising in discrimination replied saying he was happy to help anyone if you contact him. Hopefully you won’t need to and your employer will be more understanding.
Sorry if I sound a bit bossy here, my HR manager really let me down when I was isolated and stopped paying me. I had to contact my MD to get her to respond to me and give me the pay he’d promised! Stand up for yourself is my advice.