I used to use cursive in my hand written personal letters, but even that went out the window because I didn't use it enough to keep the muscle memory.
Then I only used it in my signature.
Then I stopped taking care when writing my signature.
Now my signature is a few well defined/identifiable peaks and valleys that no longer resemble any written language.
I've tested myself and I can still do it, but it takes ages to produce something worthwhile. I'm a big fountain pen user too, and apparently people think that means I have good handwriting. Nope, I just like the smoother tactile response.