It may sound crass, but it certainly helps being friends with someone of the opposite sex whom you're not at all attracted to.
My female friends always help me figure out how I've accidentally offended my girlfriend when I'm feeling particularly clueless.
Having platonic friends who identify as the same gender as your love interests is vital to maintaining a healthy relationship with your partner -- you know, the person you should be having regular sex with. This could have been avoided, I found out, through a simple conversation. Failing to properly communicate with one another isn't a problem that affects just one sex -- as is demonstrated by the eternal debate of what to have for dinner tonight.
"We have historical friends who we knew in childhood, we have common-interest friends -- the buddies we follow sports with or go to yoga with -- and then we have stage-of-life friends, college friends, just-moved-to-New York friends, friends you meet when you're a parent.
Why do women always steal our sweatshirts and then pretend like we never bought the sweatshirt in the first place? You don't want to stick anyone into a little pocket of your life." Strong friendships can persevere through everything -- including the type of romantic relationship that keeps you from your best bud for weeks at a time.
Having a platonic friend of the opposite sex gives you an abridged view of the mysteries and idiosyncrasies of that gender and might even let you know if you're doing something that's potentially annoying the hell out of your partner. So, when you have a friend who's been with you through thick and thin, that style of friendship becomes a how-to guide on ways to make sure the rest of your friends don't feel like they're being pushed aside.