Got to keep a diary but can't face it

[Brightredpencil]

GP has advised me to keep a worry diary and a general MH diary and then go back and see him in a few weeks. He's been quite good and printed me off the format forum it and everything.
I just can't face doing it. I'm a big fan of writing and journal keeping and I know studies show that Gratitude journals have have positive outcome. I have notebooks. I have pens. I can't even bring myself to write down a single word. It's difficult to describe why I feel this way. On the one hand I'm so utterly exhausted it feels like climbing Everest as well as opening flood gates and revealing too much in a "how could I possibly stop" kind of way.
Has anyone else kept a diary for this? Any tips?

Just draw a face, smiley or unsmiley. Do you think you could manage that?

I have no advice, just wanted to reply and say I get it. Sometimes when I'm depressed finding the words is almost impossible - I also feel that if I start, I'll never stop, and the deep shameful stuff comes out, or something really random which wouldn't make sense to a HCP out of the context of your life.
Maybe a very structured diary would be better, even just literally rate your mood and anxiety from 1-10, what you did that day. There are loads of apps if you search mental health tracking etc. Even that can be too much on bad days for me, relate to the utter exhaustion, but some days is better than nothing.
Good luck