There are several instances that I know of Borg who ended up free from the collective.
- Picard. Did not wish to return, which is understandable considering the brief time he was Borg.
- Seven. She did express a strong desire to at first, but then decided against it.
- Third of Five also known as Hugh. He did rejoin the collective, only to be kicked out and end up with Lore. We see in Picard that
Hugh is still an individual, with less implants, working on helping the ex Borg on board the artifact. Not a member of the collective.
So my question is are there any known ex-Borg who wished to rejoin the collective even after long term separation? If the answer is a boldfaced no, why not? Even Picard called the experience "comforting."