And here is the advice that you will never take. And then later you'll come back and say you wish you had. I never get any satisfaction out of "I told you so's."
1. The Controlling Boyfriend! Guess what? There's no such thing as a "controlling boyfriend." There's someone telling you what to do, and you going along with that. If you don't go along with it, he's not controlling you! Unless the dude has a knife to your throat, you are free to leave at any time! And there's no paperwork! Because you're not fucking married! If he's "controlling" you, I can't imagine why you think he's so precious that you want to hang around anyway.
How to avoid this situation: The first time he tells you what to do, look at him like he has 5 heads. And laugh. If that doesn't work, leave.
2. He Takes Me For Granted! Perhaps if you didn't constantly drop everything you were going to do in order to hang out with him at a moments notice, or constantly do shit for him without expecting reciprocation of any kind (except for the gloriousness of his company), he wouldn't. People, consciously or subconsciously, test you to see how far you can be pushed.
How to avoid this situation: Don't do shit for someone who isn't doing shit for you. Don't put up with shit you don't want to put up with.
3. I feel like I might want to cheat on him with this other guy that I think I like more! Then obviously, you don't like him that much. Maybe you guys shouldn't be in a relationship.
How to avoid this situation: If you want to date/make out with/ do other people, do not sign up for a committed relationship. For god sakes, it's not like car insurance!
4. I keep ending up with douchebag boyfriends! Then maybe you need to be single and work on yourself for a while.
How to avoid this situation: Once you figure out that the guy is a douche (it doesn't take that long!), stop dating him.
5. We've only been dating for a week, but we already need couple's therapy, as we have thus far racked up more problems than most people who have been married for 40 years: It's not going to get better, it's only going to get worse. The beginning of the relationship is when things should be awesome and fun and drama-free. If they suck this early on, they're going to suck a lot worse after the honeymoon period.
How to avoid this situation: Guess!
6. He's really jealous! This, actually, is not your problem. It's his. He will have to get over it. Unless, shit, you're one of those people who likes to complain/brag about how jealous your significant other is, because you think that makes other people think you're way awesome and worth desperately clinging to. Then, shit, admit that you like it and stop kvetching to me.
How to avoid this situation: Learn this phrase- "I'm sorry you feel that way." and ignore it. Don't start fights over it, don't give it any weight at all.