I don’t like the way you talk to your fiancée. She’s not your property. Her body doesn’t belong to you. Maybe she likes being exposed. Or, maybe she truly doesn’t realize that she’s revealing as much as she is, but I hardly think your arguing with her and getting “nasty” (your word!) enlightens her in a way that doesn’t immediately put her on the defense. I’d like to give you the benefit of the doubt and say your concern is all about her, but I don’t believe that’s true. I believe you think she belongs to you and is giving everyone else a peek at what is YOURS and not THEIRS. But, ok, for a second I’ll give you the benefit of the doubt for argument’s sake. I’ll pretend you just really want your fiancée to be aware that, when she wears a low-cut top and bends over, certain bras that she wears expose her nipples. Here’s how you make her aware:
You: “Honey, you might not be aware of this, but sometimes the bras you wear expose your nipples when you bend and turn in a certain way.”
Then, she can either tell you that she wasn’t aware of that or that maybe she was. Either way, your job is done. You have informed her of what you weren’t sure she was aware of. Now it’s up to her to decide whether or not to give a shit. And it sounds to me that that’s where you are now and that she has already decided not to give a shit. At this point, you can decide whether to accept that and stay with her anyway or accept that and move on because you “can’t live knowing her tits are going to be exposed.” It is not up to you to convince her to wear a different bra or ensure her nipples are never, ever revealed to anyone but you ever. Because she’s a grown woman and can wear what she wants, and can not give a shit about whatever she doesn’t give a shit about, including her areola peeking out from a bra and her fiancé having heart palpitations over the idea of anyone knowing that, indeed, she has nipples.
Spoiler alert: Most women — and men, too! — have nipples. Ironically, only one sex’s nipples can be used to feed babies and it’s that sex that is expected to keep the nipples covered at all times while the other sex walks around, nipples exposed, no questions asked, no eyebrows raised. Riddle me that, LW. What would you say to your fianceé if she told you she doesn’t want you to ever expose your nipples to anyone but her? What if she suggested that your revealing your nipples was not you exercising your freedom to do so, but actually women taking advantage of you? You’d think she was off her rocker, wouldn’t you? And why? Because men’s nipples don’t sexually titillate straight men the way women’s nipples do, right? It’s all about the reaction of straight men and catering to the reaction you either want or want to avoid. Well, fuck that.
You know who is really taking advantage of your fiancée? You are. You’re trying to take away her agency — to take away the power she employs in dressing herself for herself and making it about you and your comfort level. You are trying to employ your status and point of privilege as a man — as a straight man — to make a woman dress in a way that comforts you and makes you feel secure.
Your fiancée doesn’t need bra suggestions. What she needs is for you to quit bugging her.
If you have a relationship/dating question I can help answer, you can send me your letters at firstname.lastname@example.org.