Hi Sharon,
First of all congratulations on jumping into Real Estate Investing and welcome to the Investor family.
My opinion, after 14 years of owning rentals and working with property managers is that your property manager messed up in the screening process. However, it is very difficult to predict what a tenant will do after they move in. Most of my bad experiences with tenants came when I didn't do a thorough screening of applicants, especially checking prior landlord references.
In this case I feel sorry for the tenant who has a medical condition that is effecting her actions.
My recommendation is that you speak with the daughter and approach her from a stand point of wanting to 'HELP' her mom. It sounds like her mom would be better cared for in a residential assisted living situation rather than a condo by herself. Hopefully the daughter is mature enough to see the condition of her mom's mental state (not in denial) and help in getting her to a more appropriate dwelling.
Whatever you do, DON'T GIVE UP!!!
This is just an experience that you will learn from and although it may seem like a horrible experience, it will soon pass. Hopefully, you'll be sharing this experience with other rookie investors in the future and have a good laugh at all the events you'll be able to share.
I hope this helps and hang in there.
I would definitely ask for a discount on the management fees.
Andres