In the area you live, there is probably a group, organisation, or healthcare service that specialises in dementia.
These specialist services have great levels of knowledge about dementia disorders and will know what support is available to people with dementia and to their families.
Some of the services that are provided across the world are things like temporary residences, day care homes for people with dementia and groups of relatives, dementia cafés where people with dementia and relatives can come and enjoy themselves, as well as have a chat with peers. In some areas, there are also training courses aimed at relatives of people with dementia. These are courses that can, provide greater knowledge about how relatives best handle the changed life situation.
A good place to start is by speaking with your family doctor!