My parents are in their 80's, when should I start consider assisted living for them?

We had to go asst living with my mother-in-law when she started falling. She also stopped taking her pills the correct way, even when we had them all organized for her. She has macular degeneration, so every time she went outside to walk her driveway, I was afraid she'd fall. We set her up with a medical alert necklace, but she'd forget she had it on sometimes. She was getting meals-on-wheels 3 days a week so we'd make sure she was eating. But she didn't like the food much, so then we were back to worrying about her eating enough. After falling and breaking her hip, the doctors were all in agreement that she could no longer live alone. Now she's getting the help she needs and we no longer worry about her everyday needs. Although she still hates being there, but we can't help that. It is what it is.