my mom has dementia, what should I do?

My mom has had short term memory issues for several years. She lives at her home with my dad (who has his own issues). After yet another UTI & hospitalization, her memory is worse, confusion more pronounced. I am an only child & have to work full time to live. My husband is more or less "retired" & has been a godsend helping my folks. Both of my parents are adamant that they do not want to leave their home.
My mom was just discharged from the hospital for sepsis from a UTI. She was a handful for hospital staff as she wandered around, pulled out IV lines, etc.The had to put a bed and personal alarm on her to keep track of her.
I've resigned myself to the fact that my mom is not the mom I once knew; she is gone. It hurts horribly because the body is still here but the mind is gone..I know there is going to be a time where we can no longer care for my folks ourselves, so I'm looking into outside help to come in to assist with bathing and other tasks.
At what point do I decide that they are no longer fit to be at home?
I don't know what my specific question is, maybe I'm just rambling because I don't know what to do. What have others done?