It sounds like you are being victimized by your husband and his bank. Talk to a local attorney as soon as possible. They have no right to sell your house or make you let them show it to potential buyers. Simply filing a foreclosure action means nothing for now as first the court would have to render a judgment and then you would get six months to redeem the property. In other words, you have the right to stay at least for six month and that is only after a judgment. Get yourself some legal help.
You appear to be a victim; consult your divorce lawyer, or if you do not have one, get one and consult, as there are procedures to obtain assitance and protection.