Being married. I don't often feel this but sometimes I do. I've never said it out loud because I'm resisting marriage currently. I just think that at my age, the cons outweight the pros. But I know in my heart of hearts, a boyfriend will never be what a husband is. Not to me. And I will never feel like a wife. On the other hand, there are many things with which I needn't concern myself as a girlfriend.
That feeling of innocence I had as a kid where I could do anything and not ever imagine there might be consequences. Like running barefoot through the grass and not thinking about stepping on or in something. Or walking up to a kid I'd never met before and saying 'wanna play with me' and not think I might seem like a dork.