is it right to open your husband's social network account to sneak on him?

Sure,it is an immoral thing to do,if you ask me.May be she have some valid reasons to suspect her but using her husband's account to threaten her is not fair.And I think the husband should not have disclosed his password to her.Now it is high time for her husband to change his password and avoid misuse by her.Cheers!

How can she expect trust if she is not honest???

I think it's very immature for a wife to sneak into her husbands accounts to spy on him and his activities. If she doesn't trust him she needs to resolve why on the up and up. I don't know if their relationship needs help but she certainly does. Jealousy is a very destructive emotion. She needs to get a grip of it or her relationship will fail, and it'll be her own undoing, not his.

I think it is unfair to sneak into any one's account. She could as well talk to her husband objectively and clear her doubt. All the sneaking and trying to get 'evidence' looks like a foolish and a very round about way to do it. It is natural that she gets no proof. Firstly if the person has done no wrong, there will be no proof, secondly if he is guilty, then he will not be so naive to leave evidence to be discovered. It's a waste of time and frustrating. It can be termed a result of paranoia. Obviously such people need professional help. Now threatening is a mean and in some cases a criminal activity. She should stop it at once!