When you are single, you don't have to deal with non-family bullshit. If somebody is being rude, obnoxious, judgemental, arrogant, cruel or whatever, you can just say so, if that will make you feel better. But that isn't how a relationship works. You have to learn to bite your tongue and deal with things calmly. And relationships always result in increased responsibilities, whether it is picking him/her up, crappy family reunions, whatever.
That is why relationships suck.
The way I see it, though, just about everything sucks, but the parts that are worth it... well, they are worth it.