Would it be bad form to tell of a good friend's significant other?

[The Don]

So my friend and I were goingto get together tonight for a night of drinks, moviesand Rock Band but she has to goto her baby's father/significant other's family reunion so we've post poned until next Saturday. However it's going to be at her place since her brother is going to be in town for the weekend, but that's no biggie. My main concern is I'm going to go and her Asshat of a significant other is going to say or do something and I'm going to be forced to stand up and say or do something that will have a few possible outcomes.

1) Asshat gets pissed and leaves my friend. Good riddance in my opinion.

2) My friend get's pissed at me and wants nothing to do with me.

3) Fisticuffs.

Now one and three wouldn't bother me too much as I've been saying for the better part of two years that I'm going to stab him in the jaw with a rusty screwdriver. Not to mention very rarely have I herd her say a positive thing about him. I'm just wondering if I should go planning for the worst, if he does or says something I will have to interject, or if I should just come up with an excuse and try and reschedule.

[Aero]

why meet at her house then? thats just fucking stupid.

[The Don]

That's kinda the way I'm looking at it too. But I suppose it's one of those things she's seen the new house, she wants me to see her place... That and she's a woman, she dosen't have to make sense.

[Aero]

still tho "i want to see ur new place, but u know me and asshat don't get along. we should either go to mines, or pick a night he wont be there!" its simple, honest and shows u don't want to be the cause of any fights making u look more mature.

[jitz]

Wait you've spoken of this relationship before. You are actually sinking so low as to recycle your own old topics now.

[The Don]

You actually have standards for me, Jitz? Wow. Anyways I realized this weekend is my mother's birthday so there's my excuse.