to wonder if it might not all be entirely my fault?

[SunshineIsAMiracleCure]

I put my hands up to being rubbish and lazy around the house, although I work hard out of it to support myself and my children (no DH or DP). However when I see photographs from years ago our house looks so clean and tidy and organised, despite the children being much younger and me working much harder and longer hours.

I think things began to go wrong following a huge episode of depression, which led to repeated episodes of mood problems (both up and down) and a few admissions until it all settled thanks to the right medication. Now that I've been well for ages and ages, why can't I seem to get it together around the house? The children are helpful and co-operative but I'm not leading by example and I upset myself, plus I feel judged by various people around me (this could be all in my mind). Sometimes being untidy feels like the most morally reprehensible act in the world, then I wonder if it is why I haven't moved on and made a new life with a new partner but I don't understand why the pride I used to have in my house (not that I would ever have won any prizes for it) hasn't come back.

How do I find out if I am just lazy or if there is some unaddressed problem whether psychological, cognitive or other?

Moving house will not help you and besides your house sounds fine
I would guess the reason you don't carefully do your own dishes like you do your friends is because you don't value yourself as much as you do others. You don't think it is worth it to do your dishes carefully because only you will use them.
I think that the way you keep your house corresponds with the way you keep yourself - neglected. You sound lovely and you are being very hard on yourself posting in the AIBU section. Is there someone you can talk to?

There's also no obvious 'benefit' to doing your own stuff whereas when you do it for other people they thank you and appreciate it... it's more rewarding

We are the same here!!!

I am not a naturally tidy person - the only truly domesticated thing about me is that I live indoors!!!

I wish our house was tidier but I just can't get motivated to tidy up! I am great for leaving it until the clutter is bad and then do some extreme cleaning but rubbish at doing a little bit every day!

I had PND with DS1 and this has definitely made the apathy worse.

I get overfaced easily. I see the whole house needs to be tidied (which scares me) whereas DH sees lots of little tasks (which is more manageable).

Hope that makes sense!