Please tell me were doing the right thing 💔

We are rehoming our 7 year old bocker tomorrow who weve had since a puppy and is honestly another child to us. I feel so heartbroken and honestly like weve failed him. He has suffered with separation anxiety since after lockdown I was signed off work due to bad health. I was home alot and with him all the time and from there we just couldn't leave him as he would bark and howl non stop which resulted in complaints from the neighbours, not only that but he would become destructive we would come home to lino pulled up sofas riped apart so we stopped leaving him which meant our whole life's were put on hold. We have tried all sorts of training, doggy day care. Everything revolved around whether we could take the dog etc. We had a little boy who wants to do things where I cant always take the dog and it has become so so so hard. We also live in a flat and getting the pram and dog out is a struggle sometimes the lift in broken. We have made the decision to rehome if we are thinking of having another baby as it would be physically impossible for me to look after all three of them at once. I know for us and for our dog we are doing the right thing but its so painful 💔