If you have sat down calmly with your husband (hard to do, but yelling and screaming will not fix the problem) and he is continuing to have the affair have his bags packed and sitting at the front door and tell him she can have him and you are filing for at least a separation! This is a shock to the husband when he knows you are not going to sit around moping and enabling this behavior from him. Statistics show that husbands that have affairs do not stay in the relationship long with the mistress and most never marry them and some husbands want to come back to their wives. You're stronger than you think and you need to let him see that side of you no matter how frightening the prospect of losing him may feel to you.