Who decides whether someone needs assistance? The aging person or their family?

It sounds as though this person is still grieving the loss of her husband and is very depressed. Lots of people spend all day on their computer and it can be very therapeutic even if you are talking to people you don't know. Not taking medications and not bothering with personal hygiene are all symptoms of depression. now she has a 2 bedroom apartment perhaps you could go and stay for a few days and find out what is really going on. Nobody has the job off going round and making sure people are taking care of themselves. Outside help usually in the form of Public health only comes in when a request is made or an accident happens and the person ends up in the hospital. At that time the family and patient will be fully involved in any decision making. It sounds as though an assisted living facility would be appropriate if she truly needs supervision. If this lady was fully capable and functional before the death of her husband treating her depression and giving some grief counceling may be all she needs.