My daughter won't let me see my grandchildren

In December my 33 yr old daughter lost her job as a correctional officer because she was having an affair with an inmate. She has three children 12,8 and 6, that I have helped her raise from birth. She knew she would lose her job for this but did it anyway, knowing she was their soul bread winner, (no husband in the picture. She says she is so in love and is going to marry this inmate, who has been in prison his whole life from a teenager till now at 30 yrs old. But her plan involved moving in with me for me to take care of her and my grandchildren till he gets out. My daughter has always treated me very bad she talks to me like I am less than a pile of dog feces she criticizes everything I say and do and can not stand to be in the same room with me. She cusses me out yells screams but she also dose it to her children. She is a very unpleasant person when I pointed out what an awful mistake she made how could she do this to herself and especially her babies she went off on me she pushed me I thought she was going to hit me. I am disabled with a bad back I use a cane to walk because I fall alot, I take 120mg of morpheme daily I am always in pain. I don't sleep at night waking up every hr from the pain. I can not emotionally or physically deal with her and her drama so I told her she can not move in with me. So now she want let me see my grandchildren, want let me talk to them on the phone and has told them I do not love them and don't want them around. I know this because my 12 yr old granddaughter told her uncle, my son. My heart is broken I feel like I have let my grand babies down and turned my back on them. But I can not live with my daughter she would make my life a living hell I used to watch her three children 4 days a week when she first started working a the prison she wouldn't come home stayed out late after work and cussed and yelled at me constantly when she did get home about what I did or how I did it. I have watched them n weekends and holidays during days through the summer and she never says thank you just treats me like crap as always. I do not know why she is like this I have always tried to help her but this time it's just to much I can not live with her abuse 24/7. I feel like I have let my grand babies down and turned my back on them I worry about them so much. I know she loves them and would never hurt them physically but the verbal abuse is awful. Please someone help I just do not know what to do!

Don't be so upset, your grandchildren will be fine! If your daughter does not have any official order against you meeting the kids, may be you can meet them at their school or something? Speak to them on phone occasionally? May be write letters for them?