Finding a partner

For issues specific to caring for someone with learning disabilities

My brother is mentally disabled. He can function on his own but needs watching and help with things like cooking and cleaning.

And, he's lonely.

I was wondering if there are any forums or groups that users know of where families can get together to match-make in situations like these? I see lots of online dating sites but can't imagine that these are a good idea for someone like my brother as in this type of situation it's more of a joining of two families than it is just two people.

Any idea or advice would be greatly received.