What to do

So sorry to hear about your mum. I wouldn’t go see her, I think it might be a shock, I didn’t see my dad for the same reason, much nicer to remember her with a happy smiling face.
If your dad does want to see her maybe you could go with him and wait outside, to show your support.
Wishing you all well

I would explain exactly how you feel to your dad, that you loved your mum and want to remember her as she was. He sounds a loving man, and would understand. Don’t feel guilty, guilt is a destructive emotion. You can now support your dad with the rest of his life, which would be what your mum would have wanted.
It’s horrible when you lose your mum, whatever the circumstances, so look after yourself.

I am very sorry to hear about your mum, it still comes as a shock even amongst the relief. If it was me I would not go, she is not there, her shell is left that’s all. I would remember as she was. You will want to see your dad of course but that’s different.