Should we put mom into a nursing home?

My mother had three strokes fifteen years ago. She had 24/7 caregivers for most of that time. Due to financial problems, I am now her sole caregiver, she lives with my husband and myself. We tried two months with a sister in another state and that didn't work out. This may sound cold, but are there any guidelines as to when she should enter a nursing home? She can only transfer from chair to toilet and back and the bed. She is incontinent and completely soaked in the morning, but she rests well all night. and obviously I need my rest, Home health is coming in with OT, PT, and a Home Health aide who bathes her now; she cannot bathe herself and resents me bathing private areas. I just need some guidance as to when enough is enough.