My boyfriend and I have been together for nearly three years, and he has been suggesting the idea of a threesome for quite a while. I'm open to the idea, but at the same time I'm very worried about it because I know myself to be a very jealous person. Especially recently, he made a new friend, and I met her on Valentine's Day... Long story short, THEY cuddled, and I was left out. No sexual stuff happened, just cuddling... And it hurt me a lot. I talked to both of them about it as rationally as I possibly could... and in a casual, social setting, I'm pretty sure I'm okay with her (We've hung out a few times since), but now he really wants to have a threesome with her specifically. And he has put a lot of emphasis on the fact he wants to be the one to give her her first orgasm. She has had sex before, but she has never had an orgasm... He even asked me if I minded if he just had sex with her and I sat out... I was pretty offended, and told him so. I've been doing my best to communicate to him, but I don't know what to do (well, duh... Otherwise I wouldn't be asking this question. ^^) Previously, I was feeling more secure in the relationship, and told him that I would, and now hes saying that I can't back out... He acts like hes joking, but I know he'll be pretty hurt if I do back out. I love him very much and I want to please him (but that's not my main reason), and I'm very interested in doing what he is suggesting... I'm just not sure I'm emotionally ready to, and I'm not sure how to go about getting ready for that. Any suggestions?