So I've been doing a lot of research on stepparenting as in the next year I will become a step dad to a great 10 year old boy. His mother and I have formed a great bond and we are looking forward to moving our relationship to into a marriage.

The biological father is not really in the picture. He was an abusive figure for a long time and a habitual drug addict. At this point he needs daily methadone treatments to meet his fix. It's bad. The divorce went through early this year after the marriage had basically ended years ago. He has little contact with the stepson, but until now has been able to speak with him whenever he wants. Visitation is always supervised.

Well the proverbial shit hit the fan. The boy went to spend some time with the grandparents and conveniently the dad happened to be in the area at the same time. Until this point, the father did not know that there was a new man in the picture. The boy really likes me and I think he's phenomenal. But since he's been back he's been different and at times even negative toward me. That's completely new and I am positive it's coming from his bio dad.

Last night he called and chewed my fiance out for almost an hour in a drug induced vitriolic spew. She wouldn't hang up and he just threatened me and called her names. Then would tell her how much he missed her and loved her. She has a restraining order against the guy and he has warrants in multiple counties at this point.

He is no longer going to be allowed to see his son as she has full custody and her child's safety is of the utmost importance to her. This will remain until he can get his act together enough to be an adult. She hates keeping him from his father as she believes every child should have a father, but she won't allow it at the expense of his well being.

He has threatened me physically now that he knows I exist in the boy and his ex's life. I'm a big guy who can hold his own, but I've no interest in a physical confrontation. I'm an adult who handles things in an adult manner. I have no plans of changing my habits and I am thrilled to go through any ups and downs with this girl, but I am concerned about my relationship with the boy being strained because of venomous spew on the account of his biological father.

Has anyone gone through this before? It's not like I'm some kind of trailer trash guy here who is a threat to my girlfriend or her son. I'm a very well educated man with a great job. I've never been married, but I've fallen in love with a woman who has a great kid from a previous marriage. I'm just looking for a way to figure this out.