Simon Mason wrote
Rod Speed wrote

Even you should be able to manage to go out in
the car and do it in the car where someone who
knows nothing about you will find you

Our lass was clever - she hid the house and car keys,
even putting false keys on my own "secret" stash of
keys. I could not even get out of the windows.

Not possible to lock someone in the house forever.

Trivial to leave without the car and drink some nembutal somewhere.

Trivial to do it in your car away from home with a decent note
that makes it completely clear that it was suicide so the cops etc
dont have to waste a lot of time working out what happened.

I left them my driving licence and went
feet first, what more could they want?

A note does simplify things for them.