Did any witches/wizards (non-Squibs) ever choose to live as Muggles?

Question

This excellent question ponders whether Muggle-borns who demonstrate magical ability can choose to opt out of the wizarding world and live as Muggles. It got me thinking: are there any instances of people who have been brought up in the wizarding world choosing to forsake their magic and live as Muggles? We know of several people who grow up in the Muggle world and become wizards/witches. Not so many who go in the other direction.

The only person I can think of is Angus Buchanan but he only entered the Muggle world because he was a Squib. In other words, he had no choice.

Did anybody in the Harry Potter universe choose (either pre- or post-Hogwarts) to become a Muggle who wasn't a Squib?

Answer 1

Isobel Ross, wife of Robert McGonagall, lived as a Muggle.

Isobel Ross fell in love with and married a Muggle minister. She became a housewife, and lived with him, having given up the magical world.

Isobel and Robert moved into a manse (minister’s house) on the outskirts of Caithness, where the beautiful Isobel proved surprisingly adept at making the most of the minister’s tiny salary.
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She kept her wand in a locked box, and didn’t use magic - for a while she hadn’t even told her husband that she could.

Isobel was torn between pride and fear. She knew that she must confess the truth to Robert before he witnessed something that would alarm him. At last, in response to Robert’s patient questioning, Isobel burst into tears, retrieved her wand from the locked box under her bed and showed him what she was.
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Even after she revealed that she was a witch, she didn’t seem to return to using magic.

Now estranged from her family, Isobel could not bring herself to mar the bliss of the honeymoon by telling her smitten new husband that she had graduated top of her class in Charms at Hogwarts, nor that she had been Captain of the school Quidditch team. She sensed, too, how much of a strain it was for her mother to fit in with the all-Muggle village, and how much she missed the freedom of being with her kind, and of exercising her considerable talents.
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It’s unclear exactly how long she had lived as a Muggle, but it seemed to be quite a while - she began before her daughter was both, and seemed to be in the same Muggle village 20 years later, after Minerva had turned eighteen and spent two years working at the Ministry before becoming a teacher at Hogwarts.

Nevertheless, it was a shock to learn from the oblivious Isobel (in the middle of a chatty letter of local news) that Dougal had married the daughter of another farmer.
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It’s never mentioned if she ever went back to using magic, but she spent more than 20 years in that Muggle village, where she was “unable to exercise her considerable talents”.

Answer 2

There's someone who lived as a Muggle for only a limited time. We know very little about this, but I believe it was done as a marketing gimmick to sell a book about his struggles, similar to historical reality television shows, in which contemporary people live without modern technology for some time. The information is on J. K. Rowling's old website, in the “Wizard of the Month Archive” section

Daisy Hookum

1962 - present
Wrote bestseller 'My Life as a Muggle', after giving up magic for a year.
Married to celebrity gardener Tilden Toots.