I home educate my 'difficult' child. He was the opposite of your own, very quiet and shutdown. The change to secondary looked like a disaster in the making so we decided to keep him at home. It has taken a large committment from myself but everyday I am thankful that I followed by intuition and not my head and all those other people who said I would be mad to home educate.
To have left him in school would have continued to remove the remainder of his self-esteem and he wasn't learning at school. Its become a win-win. He's so much more confident, he is learning now and enjoying it.
We do loads of other things too which he wouldn't have had a look into at school, like woodwork, pottery, painting, tai-chi and kung-fu, guitar, recorder, singing, rock climbing ... the possibilities are endless.
There are loads of support groups and home educating groups all around the country. The one in Berkshire is particuarly amazing plus West London - all over. See the education otherwise site.
It does take 6 months after your child leaving school to really get your head around how best to teach your child and where to get all the resources you need and to connect with groups you fit with so if you do go ahead give yourself a while to get it sorted. Its so worth it.