Honestly, my house is such a mess

Try not to beat yourself up about it, JaneJudge, feel good about what you are achieving, little and often is key. Do not forget to reward yourself (not with shopping!) frequently
I'm very much the same as you Sago and for much I suspect the same reason,

Oh Sago
Always finish one job before you start another
🤔

How do you do this??? 😫

but the door shuts so all is well

I've found that just looking at my clutter drains all the energy out of my body. If anyone feels their house is a mess I'll send them a picture of mine. I'd put it on here but I'm too ashamed...

AmberGran's advice is good. I read that you're more likely to get it done if you focus on one room at a time, drawer by drawer and corner by corner. Don't think of any other room until you've completed one. Makes it seem more manageable. It's easy how builds up again though 🤣 I'm a bit like Sago as too much clutter sort of overwhelms me and I don't feel peaceful....Def something to do with childhood trauma.

However I'd love to be like you MayBee70 as I've never seen on anyone's headstone 'I wish I'd cleaned more'

Here lies a poor woman who always was tired,
for she lived in a house where help wasn’t hired.
Her last words on earth were: "Dear friends, I am going
Where washing ain't done, nor sweeping, nor sewing,
And everything there will be just to my wishes;
For where they don't eat, there's no washing of dishes.
I’ll be where loud anthems will always be ringing,
But having no voice, I’ll get clear of the singing.
Don't mourn for me now; don't mourn for me never,
For I'm going to do nothing for ever and ever.

This poem is in the public domain.
I saved this years ago although the version I saved is slightly different. Sadly though, I can't relax with the mess around me; I was a filing clerk in my youth and need everything to be neat and tidy and labelled and in it's right place. If I can't achieve that it scrambles my brain and I shut it out. My drawers and cupboards are immaculate but the bits you can see are a complete clutterfest. And instead of doing fun things like reading books with the time I spend not cleaning and tidying I just procrastinate on the internet [or sleep]. Which is what I'm doing now...

You and me both .
I find housework boring and tedious .
I've done far too much of it .
Besides it's to hot .
When I tidy -I promise myself a treat at the end of it .
I'm watching Sky Arts now and that's my treat ìn advance !

I think half the problem is having large cupboards…….we can open the door, put stuff away and it’s out of sight, out of mind! Then we just get to the stage where we have a full cupboard, of random stuff, some out of date, some outgrown, some in its wrong place and we thought it was lost.
It is quite therapeutic though, culling a cupboard!