I haven't seen the movie, but from watching the trailers... I thought Witherspoons characters was the villain of the piece. Unwittingly setting two best friends against one another and ruining their relationship as friends because she can't and won't decide which man she wants. Seemed a little selfish and misogynistic on her part just as much as it does on the two friends fighting against one another.
That said, these two can't be good friends if they let a girl who is two timing them both ruin their friendship, specially when its a girl they've only recently met. I'm pretty sure if they were that good of friends their eyes wouldn't be glaring with hatred and jealousy of each other but rather pissed off at the girl who caused it.
That said this is just my interpretation based souly on the trailer and it maybe a little unfair to judge this point given how little I've seen of the film. Though even that is in question when a trailer is there to show off the movie and reel your in.
Either way, it looked like goofy fun but from what I've heard its firmly in the "stay away" territory. Just a shame really, Tom Hardy being a pretty good actor and doing pretty well for himself that he'll have another black mark on his filmography (the first being that so-so Star Trek film he did) let's just hope he's not going to jump down into rom-com territory just yet cause that and kids movies are the slippery slope that can devour careers and actors credibility.
Speaking of Tom Hardy though, I'd be interested in hearing your thoughts on Warrior. I thought it was a pretty good film but most online critics don't seem to have given it the time of day. Which is a shame really, thought the movie deserved more and it's always interesting to see others interpretations or opinions on a movie.