NC, I haven't had an experience like that but my partner has. It deals with his mother.
When he came out, his parents cut him off, which devasted him as he was very close to his mother. They never spoke for about 3 years. Then, when they saw each other at family events, she was cordial but chill. Over time she thawed a little bit more but still strongly disliked his boyfriend at the time.
By the time he moved out here, he and his mother were getting along better but I wouldn't say that they were close anymore. His aunt on the other hand never had a problem with him being gay and openly supported him. His aunt and uncle lived here in Washington when he moved out here.
We started to date and he told me that one thing he really missed from his mother was on Valentines day she would have a special box with little goodies in it waiting for him on the bed when he came home from school. So with his aunts help, I called his mother and asked if she wouldn't mind sending the box out here so that we could continue that tradition. She was a tad bit distant with me, as she had never known me and said that she would think about it. A month later, we still didn't have the box so I called back and talked to his father. His father said that she was very attatched to the box as it had a lot of pleasant memories for her and that she wanted to keep it.
Three months later she comes out to visit her sister, my partners aunt, and the boyfriend is all nervous and trying to prepare me for her. He was very happy that she was coming out here but he kept saying over and over again how she did not like his ex-boyfriend and that I should expect the same treatment from her. I kept telling him not to worry about it.
So she comes out for three weeks and we just hit it off like we're old friends. My boyfriend kept asking here: "Who are you and what have you done with my Mother?" She even stayed with us for 3 days, too. My boyfriend couldn't believe it. They had again become as close as they were before he came out.
So she leaves and goes back home. Around the end of May, my boyfriend starts to get homesick and he books a plane flight back home for the 4th of July weekend. I'm not able to go because of work constraints.
So he gets back home, suprises his mom because July 2 is her birthday and has a great time there. He is continually shocked by everyone because they try to pump him on information about me.
Apparently, I made a huge positive impression on her and when she went back home she just talked me up like I was the best thing next to sliced bread.
So his trip home was one of the most pleasant he's had in years.
Thanksgiving comes around and we both go back to his parents. His mother insists, INSISTS, that we stay at their place. Which we didn't mind because of money constraints. Then the boyfriend is shocked even more when his mother let's us sleep in the same bed. OK, bed is a relative term. We slept on an air mattress on the living room floor. The impact on the boyfriend was still one of: "These have to be pod people."
The final unthawing came when his sister, right in front of me says: "Too bad you're dating someone now. I wanted to fix you up with a couple of my gay co-workers." I just laugh at this but later my boyfriend tells me that his sister told him to his face that he was going to rot in Hell and that he would never see his neice ever again.
So he had one of the most pleasant visits with his family he's had in years in 2006 and it's only gotten better since then.