This is all very new to me....am I doing the right things?

My dear father passed away a little over 2 weeks ago at the age of 97. My 91 year old vibrant mother was his caregiver (with the occasional visit from a nurse). Up until his passing, my mom drove, went shopping every other day, visited with friends, cooked, cleaned, organized luncheons with her group of friends (she lives in a condo), etc etc. Since his passing I have looked after everything for her (and that's OK, she needs me now); funeral arrangements, legal obligations, grocery shopping, taking her to doctor appts (she developed a cough after his passing), then blood tests and xrays, preparing her food, etc etc. I am an only child, single with no other relatives (other than 2 daughters). I dont mind and will help her anyway I can, I am considering moving to another home so we can both live there together. She has pretty well stopped eating (I go every day to make sure she eats and prepare something for her) and won't sleep. If I am not there we talk on the phone at least 5 times a day. Knowing things are bound to improve, I keep going. This morning was my first melt-down. My daughter (who temporaily lives with me) came in my room and told me to check my voice mail. My mom basically began leaving messages on both our phones starting at 5.00 am. She "slid" off her armchair and couldn't get back up. She was screaming on the messages that no one cares about her, refused to call a friend in her building, that she wishes she was dead, that she was crawling around for hours, and several messages of her just yelling HELP,etc. I immediately jumped in my car and helped her off the floor. I was shocked to see her have a cane out, a grabber and wearing adult diapers (all were left from my dad, which he needed). Not sure what to do....we are not taking any steps forward whatsoever. Is this normal behavior or has anyone experienced anything like this? Thank you so much.