Screw that crap, don't apologize for anything. I bet (and I’m guessing here) that you would really like to say to her, "what’s your damn problem biatch?", "I didn't kidnap your daughter and I don't appreciate you judging me like I’m some kind of thug just because you have bullshit issues that you want to dump all on me."

If this is the kind of thing that you would really want to say to her then fine, I understand, but that’s not what you should say at all. But definitely don't apologize for your actions. What you should say about it and all you should say to her about it is, 'I’m sorry that you are so upset about it." This lets her know that you know damn well that this crap is her problem, not yours. Just walk away when she pulls out her issues and wants to be an ass by giving you the 3rd degree about responsibility.

You will want to say all kinds of things, but just be confident that your girlfriend knows the truth and her mom is just freaking out over her own issues. If you do what these other people tell you to do then you will regret it soon trust me. What you are doing if you apologize is setting up her mom up to blame you for everything that is her problem. And when you don’t apologize for whatever her issue is then you’re just an ass now and you’re different from what you used to be.

If you choose to just apologize fine, I understand, it takes balls to follow a lot of my advice. But remember, her mom is pulling some crap on the both of you and it will only get worse until you eventually confront it. If your serious about this girl then you will tell her all this before confronting her mom. In the long run it is usually best to handle things like this from the start and not let it get worse. Don’t be afraid to be more of an adult in situations like this, I know its screwed up that you have to be more of an adult than some peoples parents sometimes but that’s life.