My own daughter rejects me...

I am 66 yr old and my daughter (the youngest of 4 - other are boys) is 39yr old. We have always been close. Her first marriage was a disaster. She married a local guy who had problems with alchole and drugs. They had a hard time with money. Later we found out why - he was using income on drugs. My husband and I have been married for 44 years, but I was the one who always picked up the pieces. My daughter had two girls, 3 and 4 when my daughter's husband decided he rather the drugs than his family. He moved out. They were living in our house that wasn't occupied at the time. They didn't pay rent and may times I had to pay their bills. My daughter and grandchildren were very close. When my daughter had to go to work, I took care of the girls. I was there whenever they needed me. She divorced her first husband, but he didn't give her any money. I supported them. They, daughter and granddaughters continued to live in our house. The husband died as a result of a drug overdose. I was still there.
My daughter met someone (a guy from Turkey) and they married. It was about that time that she started to pull away. As years went on she and her daughters grew away from us. We live in a small city and not far from each other. I am not sure if her new husband had anything to do with her pulling away, but this is where it gets strange.
On mother's day she didn't even give me a card. On father's day she made her daddy a mosaic palm tree out of broken tiles. Christmas I got nothing and she gave her daddy an expensive "bar light". She will not return my calls. I have been told not to come over unless I cal first. She allows my sister and niece to come over whenever they want to. The only time I hear from my daughter is when she needs something. Then she act like we have been great friends and that there is nothing wrong between us. She doesn't even let the girls (that I helped raise since she had no money or husband) spend any time with me. She calls her daddy on his cell phone, but not me. Trust me, I am not making this up. My son died April 26, 2006. Before he went into surgery, he asked if I would do two things.
1st, keep the family together because I was the only one who could do it and 2nd try to get closer to Beth (my daughter) since he knew that there was a problem. I still don't know the problem and I wish he would have told me.
I have been under a lot of stress (not including what I mentioned). As a result I had a complete breakdown in 2/6/07. I was unaware of what was going on around me in the hospital for two days. When I was released my daughter didn't even call or come see me for about two weeks. At the same time I was seeing therapist, psychiatrist, and was on medication. I also was taking care of my 94 yr old mother My daughter didn't even come to see her. I could go on and on. I have no clue what I did or didn't do to deserve this treatment from my only daughter. Any ideas?