Some practical ways of showing support might be to drop off meals, do their dishes, help in the garden or do some laundry. Ask what kind of support they would feel comfortable with and what might be helpful.
From speaking to carers of people living with dementia, we know that one of the most helpful things is when family and friends can be regular in their support. Can you offer to reliably share some responsibilities once a week or once a month?
This might be achieved by bringing together a small group of friends or family to create a roster.