I've been dating my boyfriend for a while now, and our relationship is fine. Okay, okay, it's not fine-I'm falling for his friend; we seem to be flirting all the time. At first I thought it was harmless, and that we were just having fun, but now I constantly fantasize about tearing his clothes off. I look forward to hanging out at my boyfriend's house because he might be there. I feel the chemistry between us, and I know he does too. I'm in a mess, and I don't know what to do. Will everyone's lives be ruined if I try to make the switch?