Alright H., listen up! Could it be that the reason Mr. Wonderful is single is because of this woman? Your guy should be telling his dad that he will not tolerate her saying bad things about his girl. You haven't given her any reason not to like you, so it isn't you, it is her! This is an issue for you, or you wouldn't be asking. If it is an issue now, it is going to be an issue later. She sounds like the kind of person who verbally abuses people because no one stops her, no one important to her, like her man of 15 years. Do you really want to subject your girls to a verbally abusive person? Do you really believe that she will always focus it on you and not them? You haven't been in this relationship long enough, these things play out in time so I suggest that if you really want to see if this relationship is going to work, you have the patience of a saint. And she is not going to change. This is going to be an issue always, is he willing to put up with the tension, including not seeing his dad if it gets to that? How he handles this will determine whether or not you think is is Mr. Wonderful, or Mr. Wonderful for a short time. In case you can't tell, my family is dealing with an issue that has some parallels to this one. How your man does, or doesn't, deal with this should be paramount to how you judge him for being a father/husband. Chin up, kiddo, you keep the control!