I just lost a custody battle and I'm not even divorced

I guess I need to explain.My marriage is intact, and our 12 year old remains in a stable home. Most of my blogs are meant to encourage parents who are training their children. This one is just for me to vent a little and maybe do some processing. It IS about parenting, however.
About 6 years ago, our family was introduced to a single mom and her two little boys. We immediately bonded with them--especially our Luke and the boys. They quickly became part of our family. They spent weekends, school breaks and most of the summers with us. They celebrated our older kids' weddings and birth of grandkids. They never missed Sunday church and big family lunches. They went on camping trips, vacations, celebrated holidays and had their birthdays with us. Their mom was frequently with us--but the boys were a given. They were in our family picture in our church directory, and had their own special foods, toys, and clothes here at our house. When they became sick at the public school they attended or forgot their homework, who did the school call? US... When they needed extra money for football registration or school trips, who did they call? US ...When they had a full week off of school, who did they call? US ...When either was sad, feeling abandoned, or worse, who held them when they cried? US .
Recently, several home factors propelled them into a foster care situation. It was incredibly difficult trying to get DCS and other entities to recognize that this white family should have any input into these young black boys' lives. After all, we weren't "FAMILY".
As the mom's parental rights were being evaluated, we were asked to begin undergoing intense background checks, home studies, and reams of intrusive paperwork. We were ready and willing to become ON PAPER that family that we had been all along.
We covered everything in prayer--and knew that God, in His perfect knowledge and sovereignty, would bring about what He planned.
And as of now, His plan is certainly not what I would have planned.
We did "lose custody" to a great aunt who is related to one of the boys. We were told it was a "cultural" decision. I know God can bring about His intent for the boys' lives, but it does not mean that I am not hurting.
Both boys introduced me to so many things : to frying bologna and hot dogs...to hair grease...to ashy skin after showers.....to hilarious trash-talking on the football field and basketball courts..to "walking the dog" dancing...to hip-hop clothing shops and hair do-rags...and sorry, boys, but I will never really like your Christian rap music :).
We introduced them to : family stability... Jesus,the Bible and church attendance...blueberry, blackberry and strawberry picking...camping....a white grandmother they also call"Nana"....growing up in the "country"....weddings in general....vegetable gardening...believe it or not, the Temptations and Michael Jackson (their favorites are "Can't Get Next To You" and "Billie Jean":).
I pray that our contact with them is not over, but we have no control over our involvement from this point. I know in my head that God can bring forth fruit where seeds are planted, but right now, I just feel empty as far as my boys are concerned. Parenting second-hand certainly has no guarantees, but I know deep down that God has His hand on them--and THAT is what will make the difference in their lives.