How can I help my dog stop barking?

I have 3 jack russell terriers and have had them all for 8 years. In the last year, one- the smallest femal has been acting out terribly. It started with her barking at the other dogs when they would sit on the couch. It progressed to her barking and biting at the others, especially the other female. About six months ago we discussed it with our vet, who helped us decide to start her on anxiety medication. Things were good with her for a few months on the medication, but have now gone back to the barking/attacking our other dogs. It’s to the point where she will bark constantly, literally non stop until she is put in her crate. She does bark sometimes in the crate also, but it never stops if she is out in the house. I am home with the dogs most of the day and I hate having her spend her time in the crate so much but I don’t have any other way to quiet her. She does not do this behavior when my husband is home, but the minute he steps out of the house it starts again. PLEASE HELP BEFORE I LOSE MY MIND FROM ALL THE BARKING!