This can lead to apathy. Frustration and its partner apathy are the enemy. Do something , even if it is a small gesture to make the resident's stay a bit more comfortable or light. Even a smile and a hello help. It is not necessary to stay long.
Brief visits are often preferred and appreciated by residents.
Reach out to other loved ones or friends for support and encouragement. If you see regular visitors to other residents, they can be valuable allies and support. Legal remedies are available for your friend or loved one who is not getting good care. You know intuitively when someone is being harmed or neglected. Listen to your feelings.