You cannot claim rent. You can only claim the portion that is related to care, not rent, that is not a medical expense. The long term care home should have those costs broken down. If it is just a retirement home where she doesn't require much care, you won't be able to claim much, the cost of staying in a residence is not something you can deduct for taxes, just like your own rent/mortgage (unless a portion under specific situations such as home business).
As @Naheulbeuck pointed out a large portion of costs are actually rent and not attendant care. If you were paying for a PSW/nurse in your home that would be purely attendant care.