There are Internet platforms where people with disabilities or their relatives can find information and exchange forums or chat rooms with those affected. Many caritative facilities also organize meetings for people with disabilities.
Self-help groups exist for different types of disabilities. Addresses of self-help groups can be found, for example, under www.nakos.de/adressen/datenbanksuche/
Help in Niedersachsen you will find here: www.familien-mit-zukunft.de/?3332399CC2975CC8AA56FFEC7A2E6272