I went to a leading public school from 16 to 18. It was a boys school that had started taking girls in the sixth form. I was a very wild girl and my mother and I couldn't say a civil word.
My parents took great trouble to find the right school. We visited six.
I hated it for the first few weeks. But then something clicked and I started to love it. The behaviour that shocked my prissy girls school was nothing special to staff who'd spent their working lives dealing with teenage boys.
I felt accepted and made lots of male (and female) friends. I spent a very happy two years there. It was a great fit. I did well academically and loved acting in the little real theatre built in the grounds.
I didn't feel abandoned at all. Instead it gave me the space I needed. I'm still grateful for the opportunity.
My two brothers were offered boarding at 11. One dived in and loved it but the other was uncomfortable so opted for weekly boarding, which worked out well.
My experience makes me feel that boarding can be a good option as long as the parents are led by the needs of their children.
Edited to add that the atmosphere in a boys school was very different from my previous school for young ladies. I got involved with the Debating Society, where my assertive speech gave me many victories. It gave me space essentially to expand.