I adopted my dog Jaya from a rescue group. Due to Jaya being almost feral and in extreme fear all the time, the lady that ran the group took her into her home for 3 months before putting her up as a 'special adoption' - saying she could only go to a 'quiet home with someone knowledgeable about dogs'
Being I was 600 miles away, I only saw Jaya in photos, but I talked with the foster lady a number of times about what Jaya was like and the difficulties that she would present being the way she was. After I sent in an adoption screening form, and some photos of my yard, fencing and interior of my house, along with my own thoughts on how I would handle this abused/feral dog, I got a phone call from the gal saying the group decided to let me have Jaya. And then she started to cry...she said she fell in love with Jaya and she was both sad to see her go, and so happy she found the right home.
We met half way...each of us driving 300 miles and met in the parking lot of a Denny's where the foster lady, transfered Jaya from her truck into the back of my sister's car...then sat back there with Jaya for about 15 minutes and cried and petted her.
I remember she kept apologizing, but my sister and I told her to take her time, and we all had tears in our eyes before it was done. It was really heartbreaking to see this woman having such a hard time in saying goodbye to Jaya.
She said she's fostered a lot of dogs, but something about Jaya stole her heart, but there was just no way to keep Jaya as Jaya needed a calm home, and this woman had a number of other fosters, plus her own dogs, and rescue group meetings at her home, along with family members and to Jaya, that was just all chaos that caused her to be on edge all the time.
About ever 3 to 4 month, I do send the gal an update on Jaya, and am very pleased that with each letter I've been able to inform her that Jaya's improved, and is now even showing me affection. Neither one of us thought that Jaya would ever be able to bond with anyone, given how much she distrusted people. It's take over two years, but I think Jaya is pleased to see me now when I come home from shopping and things like that. And she sometimes runs to me before I can even call her in from outside...and she runs with her tail up and wagging and just happy looking.
Anyway, after reading about the OP crying because missing their foster dog, I think it's time for me to send another note to Jaya's foster and just let her know that Jaya is still progressing and most of the time now, a happy and relaxed dog and to once again, thank her for saving Jaya from a kill shelter and taking her in for those 3 months which were probably very difficult given the way Jaya behaved back then.
I wish someday that the foster gal could come visit and see Jaya here in my home and see how relaxed and happy she is..as she never did get to Jaya in that way, and I think that would help her too. I mean, she knows from the letters and photos, but actually seeing it...might lighten her heart in a different way. Like I said, she was just so sad and happy at the same time in putting Jaya into my care.
It takes a special person to foster a dog...turning it over to someone who's going to give it a forever home has to be one of the most bittersweet feelings ever. But, it's due to people like that, that so many dogs get a chance to be adopted and don't have to wait around in a noisy kennel till someone adopts them.