Delusions and Hallucinations

My Mom has been getting worse everyday. She swears there are people in the trees,and all over the yard. She has it in her head that my husband gave them permission to cut trees on her property. She tells people this and that we let them live in the gazebo. At night she says they come across (the frozen lake) in boats to rescue the tree people. In reality , the lights are from homes and cars across the lake. She will stand in the doorway flicking the porch light on and off, slamming the door open and shut, and yelling at the people because "they think they are so smart hiding from the light.  Now she is feeding a "little bird", that has nail polish and jewelry on. She has decided she is afraid of my husband of 34yrs. Every time she loses something or anything goes wrong ,it's his fault. She hides everything, and accuses us constantly. She has lost her ss check, checkbooks, bank statements, ect.

I have not gotten her diagnosed, and am not sure how to go about it,now. She has never been one to go to a Dr for anything. She won't take as much as a tylenol. She has seldom been sick, and when she has been, she refused a trip to the dr. Now to take her would probly mean against her will. I work in a care home and can't believe I let it go so long. I feel lost, depressed, afraid, and haven't cried so much since losing my Dad.I also feel a bit guilty. My Mom and I have never really been close. I couldn't wait to get away, and after Dad died I found myself back with her. I want to do the best I can, and that means keeping her in her home as long as possible. I'm just not sure how to handle everything.

 What do you say when she goes on about things that aren't there? How do I handle these siuations? How do I get her diagnosed ? Once I do what then????  Help!