Never had this problem w/dogs, since I only have one and she's my 1st. However, I did have a cat (he had claimed my older female cat as "mommy")… When the "Mommy cat" died, my younger boy would meow/howl all night. I swear he woke me up at least once every hour through the night! This went on for two weeks... I was worn out!!! I hate to admit that I let him outside in total exasperation. I lived in the country in the middle of a field. He loved being free for about three days, then got bit by a snake (he didn't make it). I blame myself, I shouldn't have put him out, but I was so frustrated. Maybe I should have gotten him another older female cat, I just don't know what I should have done...
I wish I could be of more help. Surely time will help heal their pain! Hopefully you can be more patient than I was. Was your female the alpha/pack leader? Maybe they don't know what to do without her leadership...