How to cope after return/rehome?

We recently adopted an older puppy through an ethical rescue and immediately fell in love with her. She was one of the best dogs we've ever met, and though we knew she'd be a lot of work and require love and training, we were excited and committed.

There's a lot of details about what happened but in short, we finalized her adoption after an amazing week as a foster-to-adopt. Then a few days later, she showed some intense reactivity. Unfortunately, her aggression was usually without warning and aimed at our toddlers. This led to the realization that, although she'd been docile as she settled in, she was actually very anxious around the kids. I started to notice how her behavior completely changed when they entered the room.

We don't know what would have happened with more time — maybe she would have been fine, or maybe her behavior would escalate. However, since children were involved, we had to assume that her aggression would continue. Plus we now knew that while we were so happy with her, she wasn't happy with the situation.

I know that people (including me in the past!) get very judgmental about rehoming/returning dogs, but this was a textbook case where it was the right choice for everyone. We honestly could not keep her–she was stressed, our kids were starting to stress about her, and this meant we were on edge all the time. We consulted two trainers (one through the rescue and one private trainer), and the process to get her acclimated and keep the kids safe was not feasible and or fair to anyone. We'd only had her two weeks, so the absolute best choice was to return her to the rescue. The private trainer said as much and while she was willing to work with us, she told us that returning made a lot of sense given the short time we'd had her and the difficulty of making our home safe for everyone.

We know this gives her her best chance. We know she'll be happier, especially since she'll now go somewhere without small kids. It's a wonderful no-kill foster-based rescue that usually works with difficult dogs, and we know she'll find a home soon.

But we are GRIEVING. Buckets of tears, thinking about her all the time, wanting to check her page on the rescue's website, knowing we shouldn't, doing so anyway and then being sad all night. We were okay for the first week, but now it's been closer to two and it's hitting us really hard. We don't regret giving her back, but I wish we'd never met her because then we wouldn't know what we're missing. It's an odd kind of grief because she's not gone — she's out there somewhere and probably very happy, but we don't know where and we're never going to see her again, and we miss her SO MUCH. Every day we miss her.

I just don't know what to do or the best path forward. Has anyone been in this situation? Does it get better? Is there a trick to coping with this sadness?

(In case anyone mentions it–we will not be getting another dog for several years after this for a few different reasons.)