I'm certainly no expert either on dog behaviour but I might suggest a couple of things to try.. Instead of leaving Tia alone with your husband you might try walking Tia together.
This way Tia can come to realize that she is safe with you and your husband..
Also get in the floor and play with her together. or maybe you and your husband can toss one of her favorite toys to each other and maybe she'll join in on the fun play... If it works have your husband to offer her a yummy treat. Doing this a little at a time and not forcing her..
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