My daughter who is 37 and I were like best friends for years. We would shop, eat and talk on the phone for hours. I took care of her children and did as much as possible for her. Then this year it all ended. She didn't call, or answer my calls. During a fight with my husband he said that my "Negative ways had run her away." Help... I do everything I can to be positive... I have down days like everyone. I know she met a whole group of new people to be friends with... She never went any where herself before and now she is out a couple of nights a week. How can I turn this around. I am heartbroken by my failure to be a good parent.

In no way does the drop in communication make you a bad parent. She is 37 after all and perfectly capable of picking up the phone as well. Have you actually told her how you feel... that you miss talking with her? As you said, she has a new group of friends, is going out more, etc. so that will obviously take up much of her time so it would be perfectly natural for you to speak to her less often. This does not necessarily mean she cares any less, it just means her life is fuller now than it was... and it sounds like that might be a good thing. You can look at it as a chance for you to expand your interests as well.
Now, if you have any concerns about a change in behavior, for example you feel this group of new people might not be the best influence, or that she could be getting involved in something's that she shouldn't be, that would be a different story, but if it is simply the drop in time spent together, let her know. She may not even be aware of how you are feeling. Hopefully, together, you will find a balance that you both are comfortable with.

Parents are NOT good judges of how they come across to their children. My wife and I rely on each other's feedback to get a good feel for how we're doing, and we are BOTH constantly surprised when we report to each other how harsh we come across to the kids (grown kids like yours) still to this day.

Recently, my daughter called to brag about getting a new job, and I congratulated her. Later I found out I left her in tears. I had no idea. My comment during the call about her lack of cell phone (her husband took it to work and they don't have a land line at home) hit a raw nerve and wrecked her day.

I did that... during a congratulatory call! Oh my gosh!

Anyway, if you want to have any hope of truly guaging your interaction with your extended family, listen to the husband. He wants to help, he really does. Ask him not to over-critique, but from now on you WILL listen when he tries to "gentle you up" at times.

Sound fair? This is the kind of thing you can do for each other. It works wonders in my marriage, and as I've said, no one is more surprised than we are to get the unexpected feedback "That was way harsher than you meant it to be. You should try that again."

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As for your daughter, stop assuming/claiming you didn't do anything and accept that maybe you did. Try to get face to face with her so you can SEE how she reacts when you unconditionally apologize for years of being "mom" and now wanting to just be "one of the girls" if she will allow it.

Watch her, you will learn a lot just by her body language.

You can't convince her you're right about the way you treat(ed) her, she KNOWS. But you can roll out the red carpet to her. A little groveling is healthy, and if you mean it, might cure the whole situation quickly.