It might be worth checking out Face2Face: http://www.scope.org.uk/support/services/befriending/about-face-2-face
Also the National Autistic Society: http://www.autism.org.uk/get-involved/about-us/contact-us.aspx
If you think you might need respite care for your child or other services from the local authority, contact them and ask for an assessment of your child's care needs and of your needs as a carer.
Jean Merrilees BSc MRCOT
You can read more of my posts at: https://community.scope.org.uk/categories/ask-an-occupational-therapist