[Brandon]

First and foremost, you don't have threesomes with your friends. Typically, you have threesomes with people you don't know and most likely will never see again. With your boyfriend's desire to have sex with your friend, he's showing desperation. Threesomes are a lot like the process of anal sex: there's the willingness aspect of it, the knowledge of it, the execution of it, etc. For the most part, if you've never had anal sex before, you can't honestly expect the dude to be balls deep in a heartbeat. And even if that WAS the case, you shouldn't expect to enjoy it. Most people who have experienced such, myself included, know that anal is achieved through a methodical process. You can't cut corners. You can't skip steps. It usually leads to discomfort, pain, and everything else you could possibly imagine. Not to mention, it can be quite embarrassing. Same goes for alcohol. There's things you should and shouldn't do. One of those things is having threesomes with people you know. Especially friends. Especially close friends. We all check out people that aren't our partners, but it's a different situation when that person you're checking out is someone you recently had sex with; not to mention the fact that your partner watched the session with their own eyes. Threesomes take an extreme amount of trust from both partners, but you also don't want to put yourself in awkward situations, either. We all have temptations and desires, but it's unnecessary to put ourselves in situations where it encourages those temptations.

With that being said, encouragement is the word of the day here. When you get into an argument over something you are rightly upset about (him inviting a girl with you on a date), you say that he can bring a woman, but you just won't be there. Encouragement. You asked him if he wanted an open relationship, got mad at his answer, and then basically said that it's okay as long as...again, encouragement. You don't put your foot down, nor do you fully communicate to your partner. While he is wrong in many aspects, you probably could've done a few things differently since you and him have gotten back together. Threesomes don't have to make relationships fall apart, but they do because people either get the wrong impression, have them for the wrong reasons, etc. But the fact of the matter is that, absolutely, threesomes is all about sex. There's nothing romantic about it. It's straight up carnal desire. The only connection you share with your partner during a threesome is the arousal knowing your partner is aroused, and is being aroused by another human being who is enjoying both of you. Having a threesome isn't going to make the relationship better, nor will it make it worse. You react how you want to with the environment you have created. But if you play with fire, expect to get burned. If you set yourself up to fail, you will fail. It's as simple as that. Common sense.

So the fact that he's rushing into it, trying to get into friend's pants, etc is setting yourself to fail. If he doesn't desire the success of the relationship, then he'll continue to push. He'll keep poking, you'll keep arguing, and nothing will ever happen. Either you'll break up anyway, or give into him only to break up later on. The only way the relationship can succeed is if he stop being such a douchebag, focus on the woman he has in front of him (you), and be patient. If you plan on spending the rest of your life with a woman, what's the rush?