This is an interesting little film that is brave enough to tackle lesbian issues but more importantly deals with commitment--a rather universal concept regardless of the sexual orientation.
The film begins with Serena and her girlfriend preparing for Tisha's wedding. In the past, Tisha had lived the gay lifestyle, but now wanted the "straight life" with all the trappings--fancy dress, church wedding and a handsome groom. However, soon after they arrive at Tisha's house, it's obvious that Tisha is only playing lip-service to marriage--she still wants to fool around with Serena since according to Tisha "this is just fun and games...it's not cheating". This rocks Serena, because while she is gay, she has a strong need for commitment in her life. It's obvious she wants more than her promiscuous girlfriend is willing to give her.
As I said, I'm not sure why this film is rated so low. Perhaps some were uncomfortable with the Lesbian issues, but frankly the film seems much more about commitment. Plus, the idea of a gay person marrying a straight one is an important topic to discuss. I've known several cases where the gay partner lied and used their spouse--later leaving and announcing that "the straight life" isn't for them! And, since many marriages do fail due to infidelity, this, too, is a great topic for film.
An interesting adult drama that is worth a look.
By the way, the statistic spouted in the film about 1/2 of all marriages ending in divorce is deceptive. This does NOT mean 1/2 of all people who marry stand the chance of divorce--this number actually counts 2nd, 3rd, 4th, etc. marriages as well (which are much more likely to end in divorce). For first marriages, the actual percentage that end up in divorce is about 1/3--perhaps less than that. Also, the divorce rate has been rather constant in recent decades--and is actually lower than in the 1970s! Really--I'm not making this up, folks.