How do I overcome my grief and my guilt?

A fellow caregiver asked...

How do I overcome guilt from putting my mom in an assisted living. I never felt at peace about it and she cried all the time and wanted to come home. I had hoped she would find a friend or two, but she was not interested at age 91and had moderate dementia. She went down hill rapidly and died 10 weeks later. I think she died from a broken heart. I made her life so miserable the last few months by taking her out of her home.