I suspect that my girlfriend is cheating on me with my best friend. Awful, I know, but I've gotten hyper-paranoid recently and want to find out if it's true. But I don't want to ask her because (a) she might deny it even if it's true and (b) I'm not sure I can handle it if she is. What to do?
Breathe. What you've got here is a tough situation, no doubt, and you have to handle it carefully; your goal should be to get to the root of the issue while keeping yourself in tact whatever you might discover. It's better to know than to be kept in the dark, because it could hurt more later if you're right in your suspicions and you delay. You must approach your girlfriend on the subject. There's a reason she's your girlfriend, and the relationship that you have should provide for openness and honesty. If it doesn't, as you may learn, then it's not the relationship for you, ultimately. First think about why you might think this about her. Has she cheated on anyone in the past? Has she ever, to your knowledge, lied to you about anything? Are there other aspects of her life that she doesn't discuss with you? And ask yourself: am I the type of partner who provides her with a loving, honest forum in which to discuss whatever might be on her mind? Then bring it up with her. You don't need to throw out unfounded accusations that might, indeed, be rooted in the paranoia that can come on from overthinking a difficult issue like this one; you might instead approach her with something like "I always hope you can come to me with anything going on for you..." and, if she doesn't provide you any information, then say something like "I notice that you and [name of your friend] have been spending some time together. Are you attracted to her?" and see where it goes. Try and prevent her from becoming defensive by being calm and collected...certainly if you get information that makes you upset, then you'll have to honor that feeling but can hopefully do so in privacy later.