Does someone appear on a dating blacklist and become off limits once they have been… Does someone appear on a dating blacklist and become off limits once they have been involved with one of your friends? What are the rules?

LA: I think that a lot of girls would say flat out that it is never OK to hook up or get into a relationship with a friend’s ex. To me, it’s not really that simple.

LERCH: I mean, there are kind of exceptions to every rule, but in general, I would say that man laws do not really leave much room for exceptions in this case. It pretty much stands that if you have had some type of relationship with someone, she is off limits to all of your guy friends until you say otherwise.

LA: There are really two types of this so-called dating blacklisting. First would be dating/hooking up with a friend’s ex. Second would be dating/hooking up with an ex’s friend. The situations are really different, and deciding how to handle yourself if you develop feelings for someone who is “off limits” depends a lot on your relationships with all parties involved. But advice for what to do in such situations kind of applies either way, so for our purposes, let’s say that you are interested in someone who used to date a friend of yours.

LERCH: First of all, it depends on who you consider a friend. For instance, if you’re interested in the two-week-long ex-hookup of a guy who lives on your floor who you only say hi to in passing, then she is fair game. If she is the ex-girlfriend of your roommate or someone whose friendship actually means something to you, then it’s a different story.

LA: You have to weigh out what is more important in the long run – and I repeat, the LONG RUN. Think about how long you have been friends with the person who you might end up hurting here, and how betrayed or hurt she will feel if you start getting involved with someone who meant a lot to her.

LERCH: If it’s a friend who has constantly been there for you and whom you’ve always been able to count on, it’s probably not worth it. There is the chance that this new fling could end up being your future spouse, but it’s pretty slim. And there are other fish in the sea. But if you don’t consider your friendship with the person to be of particular value, and you see real potential with this new hook up, then go for it.

LA: If you are considering throwing away a friendship, you should first consider what happened that caused your dear friend’s relationship with this person to end in the first place. If the ex didn’t treat your friend well or cheated on her, it is likely that he will do the same to you. And if your friend was the one who ended the relationship, you should think about why that was.

LERCH: Time is a factor, too. If we’re talking about your friend’s girl from freshman year of high school, then it’s probably safe to say that they’ve moved on by now and that the girl is up for grabs. Also, if the friend in question is in a new, more serious relationship, he might be cool with you stepping on his old turf. But it’s always best to check and not make assumptions either way. The simplest way is to be straight up about the way that you feel. But if you check with your friend and he isn’t cool with you dating his ex, then that’s the end of the discussion right there. Bros before hoes, chicks before dicks, all that good stuff.

LA: If the person values your friendship as much as you do, then she will respect the fact that you asked how she felt and valued her opinion. If one of my friends showed genuine interest in a guy who I knew I would never be with again and hadn’t had particularly strong feelings for, then I might give her the go ahead. But don’t ask if it isn’t going to make a difference in your decision. If you’re totally convinced that you are going to start a relationship with the person who used to date your friend regardless of how it will affect your friendship, then be fair and let the person know so she doesn’t have to hear it from someone else. But be prepared for the friendship to end.

LERCH: And of course, there are certain situations where you absolutely positively cannot cross that line, to the point where it isn’t even appropriate to ask. No matter what your feelings are, you cannot start something with the girl who just crushed your lifelong best bud’s heart. When you risk friendships, it’s not necessarily only that particular friendship that is gonna end. If you screw over one of your friends, all of your mutual friends will probably lose trust in you.

LA: So if you’re going to violate the laws, be sure it’s really worth it. A drunken one night stand? Not worth it. Being drunk is not an excuse – just like it’s not an excuse for cheating. Think about what you want to get out of this hook up and what you’re already getting out of your friendships. Don’t jump to conclusions either way, and be honest as soon as you have the feelings. If rumors start flying, you’ve got a whole new set of problems.

E-mail Leigh Ann and Keith with questions or comments at [email protected].