@Siewli many of us can relate to how you are feeling and I agree with the tips that have been shared. I saw a psychologist at the start of my treatment as I just could not get my head straight - it is such a mind game as well as a physical challenge. I found that being able to speak openly with someone who did not have the emotional connection to me invaluable. I know the mental health system is stretched at the moment, and it may be difficult to get an appointment, but the cancer council also offers free services - I used them too and they were also excellent. Your family members can also use this service.
I also set up a calendar and I used a big red pen to mark off each treatment - simple, but it really helped me to see the progress. Try to only focus on one round at a time, don’t get ahead of yourself. You are going to find your own routine as you will start to know what your good days are and which days you may need to just lie on the couch.
On your better days, try to do something nice, something that makes you happy - sitting outside, going for a drive, anything at all. If you can, try to go for a walk - even on the days when you don’t feel like it - just a really gentle stroll. Definitely keep your treating team informed of your symptoms as they will be doing their best to keep you as comfortable as possible.
You are going to get through this - in fact, you are going to be amazed at just how strong you are. You are brave - never doubt that. You are also stronger than you believe. You can do this.